Pump Raspberry [Discontinued] by ProMera Sports

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Alcohol use disorder. Although there has been interest in using oral agmatine for alcohol use disorder, there is insufficient reliable information about the clinical effects of agmatine for this purpose.
• Alzheimer disease. Although there has been interest in using oral agmatine for Alzheimer disease, there is insufficient reliable information about the clinical effects of agmatine for this purpose.
• Anxiety. Although there has been interest in using oral agmatine for anxiety, there is insufficient reliable information about the clinical effects of agmatine for this purpose.
• Athletic performance. Although there has been interest in using oral agmatine for improving athletic performance, there is insufficient reliable information about the clinical effects of agmatine for this purpose.
• Autism spectrum disorder. Although there has been interest in using oral agmatine for autism spectrum disorder, there is insufficient reliable information about the clinical effects of agmatine for this purpose.
• Bipolar disorder. Although there has been interest in using oral agmatine for bipolar disorder, there is insufficient reliable information about the clinical effects of agmatine for this purpose.
• Depression. Although there has been interest in using oral agmatine for depression, there is insufficient reliable information about the clinical effects of agmatine for this purpose.
• Epilepsy. Although there has been interest in using oral agmatine for epilepsy, there is insufficient reliable information about the clinical effects of agmatine for this purpose.
• Herniated disc. It is unclear if oral agmatine is beneficial in patients with herniated disc. Details: A small clinical study in patients with radicular pain associated with lumbar disc herniation shows that taking agmatine sulfate 890 mg three times daily for 14 days decreases pain scores by around 20% and increases health-related quality of life scores by around 50% when compared with placebo (94736).
• Muscle strength. Although there has been interest in using oral agmatine for increasing muscle strength, there is insufficient reliable information about the clinical effects of agmatine for this purpose.
• Parkinson disease. Although there has been interest in using oral agmatine for Parkinson disease, there is insufficient reliable information about the clinical effects of agmatine for this purpose.
• Peripheral neuropathy. It is unclear if oral agmatine is beneficial in patients with peripheral neuropathy. Details: A small, open-label study in patients with peripheral neuropathy of mixed etiologies shows that taking a specific agmatine sulfate product (AgmaSet, Gilad&Gilad LLC) 2.67 grams daily, in divided doses, for 2 months reduces pain intensity by around 46% and improves symptom scores for burning, numbness, and tingling when compared to baseline (111144). The validity of these findings is limited by a lack of comparator group.
• Schizophrenia. Although there has been interest in using oral agmatine for schizophrenia, there is insufficient reliable information about the clinical effects of agmatine for this purpose.
• Stroke. Although there has been interest in using oral agmatine for neuroprotection against stroke, there is insufficient reliable information about the clinical effects of agmatine for this purpose. More evidence is needed to rate agmatine for these uses.

(Read more about AGMATINE)

POSSIBLY EFFECTIVE

• Chronic kidney disease (CKD). Oral alpha-ketoglutarate appears to improve markers of amino acid metabolism and prevent secondary hyperparathyroidism in patients with CKD on hemodialysis. Details: Several small clinical studies in patients on hemodialysis show that taking calcium alpha-ketoglutarate seems to improve biochemical markers, including blood levels of urea and phosphate, when compared with pre-treatment (5311,30784,30785). Furthermore, one small clinical study shows that taking calcium alpha-ketoglutarate 4.5 grams daily for 36 months decreases serum levels of parathyroid hormone in these patients, suggesting that calcium alpha-ketoglutarate might decrease the risk of secondary hyperparathyroidism (30785).

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Aging. It is unclear if oral alpha-ketoglutarate can prevent signs and symptoms of aging. Details: A small observational study in healthy adults has found that taking a specific product (Rejuvant, Ponce De Leon Health Inc.), providing calcium alpha-ketoglutarate 2 grams and vitamin A 900 mg (males) or vitamin D 25 mg (females), daily for 4-10 months is associated with an 8-year reduction in biological age, as measured by DNA methylation testing (111124). The validity of these findings is limited by a lack of randomization and placebo control.
• Aging skin. It is unclear if topical alpha-ketoglutarate is beneficial in patients with aging skin. Details: A small clinical study in healthy Chinese females shows that applying alpha-ketoglutarate cream to the face daily for 8 weeks improves skin firmness and reduces the severity of crow's feet wrinkles, nasolabial folds, and forehead skin wrinkles when compared to baseline (111125). The validity of these findings is limited by a lack of control group.
• Athletic performance. It is unclear if oral alpha-ketoglutarate improves athletic performance. Details: A small clinical trial in adults shows that taking alpha-ketoglutarate (Evonik Rexim SAS) 0.2 grams/kg daily for 5 weeks increases exercise tolerance, power output, and muscle torque when compared with placebo (18113). Another small clinical study in middle-distance runners 14-17 years of age shows that taking a specific L-arginine alpha-ketoglutarate product (AAKG 1250 Extreme Mega Caps, Olimp Laboratories) 2.5-3.75 grams, combined with a calcium hydroxymethylbutyrate product (HMB 1250 Mega Caps, Olimp Laboratories) 2.5 grams, 3 times daily attenuates reductions in countermovement jump height during a 12-day intensive training camp when compared with placebo. Markers of muscle damage and stress were similar in both groups (106032). It is unclear if the findings from this study are due to alpha-ketoglutarate, other ingredients, or the combination.
• Bariatric surgery complications. Although there has been interest in using oral alpha-ketoglutarate for bariatric surgery complications, there is insufficient reliable information about the clinical effects of alpha-ketoglutarate for this purpose.
• Idiopathic interstitial pneumonia. Although there has been interest in using oral alpha-ketoglutarate for idiopathic interstitial pneumonia, there is insufficient reliable information about the clinical effects of alpha-ketoglutarate for this purpose.
• Inflammatory bowel disease (IBD). Although there has been interest in using oral alpha-ketoglutarate for IBD, there is insufficient reliable information about the clinical effects of alpha-ketoglutarate for this purpose.
• Ischemia-reperfusion injury. It is unclear if intravenous alpha-ketoglutarate can prevent ischemia-reperfusion injury during or after heart surgery. Details: A small clinical study in male patients undergoing heart surgery shows that intravenous administration of alpha-ketoglutarate 28 grams with blood cardioplegia reduces several markers of ischemia when compared with a control group, suggesting that alpha-ketoglutarate might prevent ischemic injury during heart surgery (5312,5313).
• Liver disease. Although there has been interest in using oral alpha-ketoglutarate for liver disease, there is insufficient reliable information about the clinical effects of alpha-ketoglutarate for this purpose.
• Osteoarthritis. Although there has been interest in using oral alpha-ketoglutarate for osteoarthritis, there is insufficient reliable information about the clinical effects of alpha-ketoglutarate for this purpose.
• Osteoporosis. Although there has been interest in using oral alpha-ketoglutarate for osteoporosis, there is insufficient reliable information about the clinical effects of alpha-ketoglutarate for this purpose.
• Rheumatoid arthritis (RA). Although there has been interest in using oral alpha-ketoglutarate for RA, there is insufficient reliable information about the clinical effects of alpha-ketoglutarate for this purpose.
• Small intestinal bacterial overgrowth (SIBO). Although there has been interest in using oral alpha-ketoglutarate for SIBO, there is insufficient reliable information about the clinical effects of alpha-ketoglutarate for this purpose.
• Tendinopathy. Oral alpha-ketoglutarate has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small clinical study in patients with insertional Achilles tendinopathy shows that taking two sachets of a specific combination product (Tenosan, Agave s.r.l.), each containing methylsulfonylmethane 550 mg, arginine-L-alpha-ketoglutarate 500 mg, hydrolyzed collagen type I 300 mg, Vinitrox 125 mg, bromelain 50 mg, and vitamin C 60 mg, in addition to extracorporeal shock wave therapy (ESWT) improves pain and function when compared with ESWT alone (19321). It is unclear if these findings are due to alpha-ketoglutarate, other ingredients, or the combination. More evidence is needed to rate alpha-ketoglutarate for these uses.

(Read more about ALPHA-KETOGLUTARATE (AKG))

POSSIBLY EFFECTIVE

• Athletic performance. Small studies show that taking a single oral dose of L-citrulline before anaerobic resistance exercise might reduce exhaustion and improve some performance measures. It is unclear if L-citrulline improves aerobic exercise performance; results are conflicting. Details: A meta-analysis of small clinical trials in healthy trained and untrained adults shows that taking L-citrulline prior to mostly anaerobic exercise marginally reduces perceived exhaustion and muscle soreness when compared with placebo (105965). Another meta-analysis including some of the same clinical studies shows that taking L-citrulline malate before exercise modestly increases performance on resistance exercises by an average of 6% when compared with placebo (105968). Individual studies show mixed benefit and mostly use a single dose of L-citrulline malate 8 grams 1 hour before exercise; other studies used L-citrulline 3.3-6 grams mixed in watermelon juice or sucrose water or L-citrulline malate 12 grams given 1-2 hours before exercise (94966,94957,97395,105965). L-citrulline has also been evaluated for use with aerobic exercise. A small study in healthy young adults taking L-citrulline 9 grams in 3 divided doses over 24 hours or as a single dose of 3 grams 3 hours before a treadmill test does not improve performance, but might reduce time to exhaustion, when compared with placebo (16473). Another small clinical study in healthy adults shows that taking about 6.8 grams (100 mg/kg) of L-citrulline daily for 5 days prior to a cycling trial does not improve time to exhaustion, oxygen uptake, or lactate levels when compared with taking 3 grams of glucose as placebo (105964). However, two small clinical trials in healthy males show that taking L-citrulline 2.4-6 grams daily for 7 days prior to a cycling test improves peak power by 9%, total work by 7%, and cycling time trial performance by 1.5% when compared with placebo (94954,94965). Differences in methods of testing athletic performance, the form and dose of L-citrulline used, and/or the duration of supplementation may explain the mixed results. L-citrulline has also been evaluated in combination with L-arginine. Research in male soccer players shows that taking L-citrulline 1.2 grams and L-arginine 1.2 grams daily for 7 days increases total power output over a 10-minute cycling test and improves subjective perceptions of exertion when compared with placebo (100956).

POSSIBLY INEFFECTIVE

• Sarcopenia. Oral L-citrulline does not seem beneficial for muscle strength in older adults when added to structured exercise. Details: Two small clinical studies in older adults show that taking L-citrulline in conjunction with structured exercise does not improve measures of strength, endurance, speed, or balance when compared with placebo and structured exercise (110146,110148). One study evaluated otherwise healthy adults aged 60-73 years taking L-citrulline 3 grams daily for 6 weeks (110146). The other study evaluated older adults with obesity and an average age of 68.5 years taking a specific L-citrulline product (Citrage) 10 grams daily for 12 weeks (110148).

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Cardiovascular disease (CVD). Although there is interest in using oral L-citrulline for CVD, there is insufficient reliable information about the clinical effects of L-citrulline for this condition.
• Dementia. Although there is interest in using oral L-citrulline for dementia, there is insufficient reliable information about the clinical effects of L-citrulline for this condition.
• Diabetes. It is unclear if oral L-citrulline is beneficial in patients with diabetes. Details: A small clinical study in adults with diabetes who are taking metformin and sulfonylureas shows that adding L-citrulline (Bulk Supplements Co., Ltd.) 3 grams daily before breakfast for 8 weeks reduces average fasting blood glucose levels by 22 mg/dL and glycated hemoglobin by 0.7%, but does not affect lipid levels, when compared with taking a microcrystalline cellulose placebo (105963).
• Erectile dysfunction (ED). It is unclear if oral L-citrulline is beneficial in patients with ED. Details: A small non-randomized crossover study in adults with mild ED shows that taking L-citrulline 1.5 grams daily for one month improves erection hardness from "mild dysfunction" to "normal function" in 50% of patients, compared with only 8% of patients taking placebo (94956). L-citrulline has also been evaluated in combination with other ingredients. A clinical study in middle-aged males with ED shows that taking a specific combination product (Revactin, MD Concepts LLC) containing L-citrulline, muira puama, ginger root, and guarana twice daily for 3 months improves scores related to erectile function and intercourse satisfaction, but does not improve sexual desire or orgasmic function scores, when compared to baseline (103224). The validity of this study is limited by the lack of a placebo control, the use of per-protocol analysis, and a high dropout rate. In fact, 44% of patients withdrew in order to resume use of phosphodiesterase type 5 (PDE5) inhibitors. Another small clinical study in adults with ED living in Japan and using PDE5 inhibitors as needed shows that taking an adjunct 50 mL drink containing L-citrulline 800 mg, a specific fenugreek extract (Testofen) 600 mg, resveratrol 300 mg, and caffeine 40 mg daily for 14 days modestly improves erectile function and satisfaction with intercourse and orgasm when compared with a placebo drink (105966). The validity of this finding may be confounded by the "as needed" use of PDE5 inhibitors, which was not reported throughout the study. Further, in both combination studies, it is unclear if these effects are due to L-citrulline, other supplement ingredients, or the combination.
• Heart failure. Small clinical studies suggest that oral L-citrulline might be beneficial in patients with heart failure. Details: A very small clinical study in patients with heart failure with preserved ejection fraction (HFpEF) shows that taking L-citrulline malate 3 grams daily for 2 months decreases systolic pulmonary arterial pressure by 16% and improves the right ventricular ejection fraction after a stress test by 27% when compared to baseline (94962). The validity of this finding is limited by the lack of a control group. Another small open-label clinical study in patients with heart failure with reduced ejection fraction (HFrEF) shows that taking L-citrulline 3 grams daily for 4 months increases left ventricular ejection fraction by about 20% at rest and 13% during the stress test, and increases the right ventricular ejection fraction by about 15%, both at rest and with the stress test, when compared with no supplementation. This improved the heart failure functional class in 35% of patients (94955).
• Hypertension. It is unclear if oral L-citrulline is beneficial for lowering blood pressure. Details: A small clinical trial in adults with prehypertension shows that taking L-citrulline 2 grams with grape and cranberry polyphenols 548 mg daily for 6 weeks does not reduce mean ambulatory blood pressure when compared with a cellulose placebo (105969). A small crossover study in postmenopausal females with hypertension shows that taking L-citrulline 6 grams as a single dose does not improve systolic or diastolic blood pressure at rest or during 5 minutes of plantar flexion exercise when compared with placebo (110147). The effects of using L-citrulline regularly or in other patients with diagnosed hypertension is unclear.
• Lysinuric protein intolerance. Although there is interest in using oral L-citrulline for lysinuric protein intolerance, there is insufficient reliable information about the clinical effects of L-citrulline for this condition.
• Muscle strength. It is unclear if oral L-citrulline can improve muscle strength when used in conjunction with resistance training. Details: A clinical study in healthy resistance-trained adults shows that taking L-citrulline malate 2 grams daily for 8 weeks in conjunction with resistance training does not further increase lean mass or muscle strength, measured by leg and bench presses, when compared with a cellulose placebo and resistance training (97394).
• Muscular dystrophy. It is unclear if oral L-citrulline is beneficial in patients with Duchenne muscular dystrophy. Details: A small clinical study in adults with Becker muscular dystrophy, a milder form of Duchenne muscular dystrophy (DMD), shows that taking L-citrulline 5 grams with or without metformin 500 mg three times daily for 6 weeks improves 6-minute walking distance and decreases markers of muscle necrosis when compared to baseline (100975). A small clinical study in males aged 6.5-10 years with DMD shows that taking L-citrulline 2.5 grams with metformin 250 mg three times daily for 26 weeks does not appear to slow decline in motor function when compared with placebo. However, this combination seems to slow decline in children with more stable disease, defined as those who can walk at least 350 meters in 6 minutes (100976). The reasons for these disparate results are unclear, but they may be due to the different patient populations, disease severities, doses, and durations of therapy being studied.
• Postoperative pulmonary hypertension. It is unclear if oral citrulline prevents postoperative hypertension in children undergoing heart surgery. Details: A small clinical study in children 6 years of age and younger undergoing congenital heart surgery shows that higher blood levels of L-citrulline might protect against the incidence of postoperative hypertension. L-citrulline blood levels of at least 37 micromol/L immediately after surgery, and at 12, 24, and 36 hours postoperatively, protects against its development. However, supplementation with 1.9 grams/m2 during induction of anesthesia is not necessarily protective (16467).
• Post-polio syndrome. It is unclear if oral L-citrulline is beneficial for patients with this condition. Details: A small clinical study in adults with post-polio syndrome shows that taking L-citrulline 5 grams three times daily for 24 weeks does not improve 6-minute walking distance, motor function scores, muscle strength, or quality of life when compared with placebo (110149).
• Pulmonary hypertension. It is unclear if oral L-citrulline is beneficial in patients with pulmonary hypertension. Details: A very small clinical study in patients with idiopathic arterial pulmonary hypertension or pulmonary hypertension due to Eisenmenger syndrome shows that taking L-citrulline malate 1 gram three times daily for 2 weeks increases 6-minute walking distance by 44 meters and reduces mean pulmonary arterial pressure by 5% when compared with baseline (94963). The validity of these findings is limited by the small study size and the lack of a comparator group.
• Reye syndrome. Although there is interest in using oral L-citrulline for Reye syndrome, there is insufficient reliable information about the clinical effects of L-citrulline for this condition.
• Sickle cell disease. It is unclear if oral L-citrulline is beneficial in patients with sickle cell disease. Details: A small clinical study in children ages 10-18 years shows that taking L-citrulline 90-130 mg/kg daily in 2 divided doses for up to 9 months might reduce neutrophilia and other symptoms when compared with baseline (16463). The validity of these findings is limited by the small study size and the lack of a comparator group. More evidence is needed to rate L-citrulline for these uses.

(Read more about L-CITRULLINE)

POSSIBLY EFFECTIVE

• Asthma. Oral maritime pine bark extract, taken as an adjunct to conventional asthma medications, may improve symptoms and reduce rescue inhaler use in patients with asthma. Details: Three small clinical studies in children and adults with asthma of varying severity show that taking a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 1 mg/lb body weight or 100 mg daily in addition to conventional asthma medications increases peak expiratory flow, decreases asthma symptoms, and decreases the need for rescue medications when compared with conventional therapy alone (13120,50863,50926). Maritime pine bark extract has not been studied as monotherapy for asthma and should not be used in place of conventional medicine for this purpose.
• Chronic venous insufficiency (CVI). Oral maritime pine bark extract may improve leg pain and heaviness and reduce edema in patients with CVI. Details: Several clinical studies in patients with CVI show that taking a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) reduces edema, the rate of ankle swelling, and symptoms of leg pain and heaviness when used for 3-12 weeks. The most commonly used dose is 100-120 mg three times daily (2451,2462,2493,7693,50892). However, lower doses of 50 mg three times daily (16906,50892,50900,50915) or 45-100 mg once daily also seem to be effective (2435,97401). When compared with the use of below-knee compression stockings worn throughout the day, maritime pine bark reduces induration and the rate of ankle swelling when compared to baseline in patients with CVI. While both treatments reduce venous edema and pain when compared with baseline, a more pronounced reduction is seen in patients taking the maritime pine bark extract (97401). Other clinical research in adults who have had CVI for more than 3 years shows that taking the same extract, 50 mg three times daily for 8 weeks, in addition to wearing compression stockings, improves microcirculation and subjective symptom scores when compared with compression stockings alone (103616). However, compliance with the use of compression stockings in this study was poor.
• Osteoarthritis. Small clinical studies suggest that oral maritime pine bark extract may modestly improve symptoms and reduce the need for analgesics in patients with knee osteoarthritis. Details: Two small clinical studies in patients with knee osteoarthritis shows that taking a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 100-150 mg daily for 3 months reduces overall osteoarthritis symptoms, pain, and the use of anti-inflammatory medication when compared with placebo (50903,50905). Topical maritime pine bark has also been evaluated. Observational research in patients with knee osteoarthritis found that applying standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 220 mg, as two patches daily, for three weeks is associated with reduced pain and reduced need for rescue analgesics when compared with control (100356).

POSSIBLY INEFFECTIVE

• Hyperlipidemia. Oral maritime pine bark extract may not improve lipid levels in patients with hyperlipidemia. Details: Although individual clinical trials have shown mixed results (7693,91965,97408), a meta-analysis of 4 small clinical trials in patients with hyperlipidemia shows that taking a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 100-150 mg daily for 4-24 weeks does not reduce total cholesterol, low-density lipoprotein (LDL) cholesterol, or triglyceride levels when compared with a control (100357).

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Age-related cognitive decline. It is unclear if oral maritime pine bark extract is beneficial in elderly patients with age-related cognitive decline. Details: One observational registry study in healthy elderly patients ages 55-70 years has found that taking a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 100 mg daily for 12 months is associated with improved cognitive function, mental performance, and attention when compared with matched controls (97405). However, the validity of these findings is limited by the unblinded, non-randomized nature of the study. Also, a small clinical study in healthy elderly patients 60-85 years of age shows that taking the same extract, 150 mg daily for 3 months, improves spatial working memory, but not numeric working memory, episodic memory, attention, or psychomotor performance, when compared with placebo (50906).
• Aging skin. Although there has been interest in using oral and topical maritime pine for aging skin, there is insufficient reliable information about the clinical effects of maritime pine for this purpose.
• Allergic rhinitis (hay fever). It is unclear if oral maritime pine bark extract is beneficial in people with allergic rhinitis. Details: A small clinical study in patients with birch allergies shows that taking a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 50 mg twice daily, starting at least 5 weeks before allergy season, decreases nasal symptoms associated with birch allergies when compared with placebo (17300).
• Androgenic alopecia. It is unclear if oral maritime pine bark is beneficial for androgenic alopecia. Details: A small clinical study in postmenopausal patients conducted in China shows that taking maritime pine bark (Pycnogenol, Horphag Research) 150 mg daily for 6 months improves hair density when compared to baseline (112713). However, the interpretation of these findings is limited by the lack of a statistical comparison to the placebo group.
• Antidepressant-induced sexual dysfunction. It is unclear if oral maritime pine bark is beneficial for improving sexual function in adults taking escitalopram. Details: A small, open-label clinical study shows that taking standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 50 mg daily for 4 months with escitalopram 10-20 mg daily seems to improve sexual dysfunction when compared with escitalopram alone (100361).
• Atherosclerosis. Oral maritime pine bark extract has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A non-randomized clinical trial in adults with atherosclerosis shows that taking a specific maritime pine bark product (Pycnogenol, Horphag Research) 150 mg and gotu kola 225 mg, in two divided doses daily for 3 months, reduces plaque height and length and increases plaque echogenicity and stability when compared to control (97030). However, these benefits may be at least partially due to gotu kola. Another non-randomized clinical study in adults with atherosclerotic plaques and no other cardiovascular risk factors shows that taking Pycnogenol 100 mg and gotu kola extract 100 mg daily for up to 4 years reduces plaque progression and increases plaque echogenicity to a greater extent than Pycnogenol alone or no treatment at all. Taking Pycnogenol with gotu kola is also associated with a reduced rate of clinical vascular events, including angina, myocardial infarction, minor transient ischemic attacks (TIAs), and minor strokes, when compared with taking Pycnogenol alone or receiving no treatment at all (97029).
• Athletic performance. It is unclear if oral maritime pine bark extract is beneficial for improving exercise capacity in recreationally trained adults; the available evidence is conflicting. Details: One small clinical study shows that taking a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 200 mg orally daily for 30 days improves exercise capacity during a treadmill test in recreational athletes aged 20-35 years (2554). Additionally, an observational registry study found that taking this same maritime pine bark extract 100 mg orally daily for 8 weeks along with training improves performance in the Army Physical Fitness Test, including reducing two-mile treadmill time by about 45-60 seconds and increasing the number of push-ups and sit-ups by about 5-7 when compared to control training alone. Taking this maritime pine bark extract during training also appears to improve total triathlon time by about 6 minutes when compared with training alone (91966). However, the validity of this finding is limited by the unblinded, non-randomized nature of the study. Additionally, a small study in college-age males who exercise regularly shows that taking the same maritime pine bark extract 800 mg daily, starting 14 days prior to a cycle ergometer test and continuing for 2 days after, does not improve maximum oxygen consumption or power generated in the test when compared with placebo (103617). Maritime pine extract has also been studied in combination with other ingredients. A small clinical study in non-professional athletes shows that taking a combination product (PycnoRacer, Kobayashi Pharmaceutical Company) containing maritime pine extract 15 mg, L-leucine 0.6 grams, L-arginine 0.3 grams, L-isoleucine 0.3 grams, and L-valine 0.3 grams four times daily for 3 weeks during training improves running distance by about 19%, compared with 9% in athletes drinking water plus Gatorade. Maritime pine park also improved maximal oxygen consumption and reduced subjective scores of muscle pain and cramps when compared with water and Gatorade (103613). It is unclear if these benefits are due to maritime pine, other ingredients, or the combination.
• Attention deficit-hyperactivity disorder (ADHD). It is unclear if oral maritime pine bark extract is beneficial in children or adults with ADHD. Details: A small clinical study in adults with ADHD shows that taking a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) does not seem to improve ADHD symptoms when compared with placebo (9984). However, a small clinical study in children with ADHD shows that taking this standardized maritime pine bark extract 1 mg/kg daily for one month appears to improve attention and hyperactivity scores when compared with placebo (50891).
• Behcet syndrome. It is unclear if oral maritime pine bark extract is beneficial in patients with Behcet syndrome. Details: A small clinical study in patients with Behcet syndrome shows that taking a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 150 mg daily for 3 weeks reduces skin ulcer size and improves self-reported symptoms of burning and pain when compared to baseline (100358). The validity of these findings is limited by the lack of a comparator group.
• Benign prostatic hyperplasia (BPH). It is unclear if oral maritime pine bark extract is beneficial in patients with BPH. Details: A small observational registry study in patients with BPH found that taking a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 150 mg daily for 8 weeks is associated with modest improvement of symptoms such as bladder emptying, urgency, flow, straining, and nocturia (100359). This study was limited by small size, reporting inaccuracies, and its unblinded, non-randomized design.
• Cognitive function. Small clinical studies suggest that oral maritime pine bark extract might improve cognitive function in healthy adults. Details: A small observational registry study in healthy adults aged 30-55 years found that taking a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 150 mg daily for 12 weeks is associated with slightly improved memory and cognition when compared with matched controls (97410). However, the validity of these findings is limited by the unblinded, non-randomized nature of the study. A small clinical study in healthy college students also shows that taking the same extract 100 mg daily for 2 months seems to reduce failed tests by 4.5% and improve average test scores by about 8% when compared with control (50928).
• Cognitive impairment. It is unclear if oral maritime pine bark extract improves cognitive function in patients with mild cognitive impairment. Details: An observational registry study in adults with mild cognitive impairment found that taking a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 150 mg daily for 8 weeks improves global cognitive function when compared to no supplementation. All patients in this study also received standard management of mild cognitive impairment, which included lifestyle modifications such as improved sleep, physical exercise, reduced sugar and salt intake, lowering cardiovascular risk factors, and avoiding use of stimulants or depressants (97406). However, the validity of these findings is limited by the unblinded, non-randomized nature of the study.
• Common cold. It is unclear if oral maritime pine bark extract is beneficial in the treatment of the common cold. Details: An observational registry study in otherwise healthy adults with a cold found that taking a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 50 mg twice daily, along with best management for colds, is associated with about one less day of a perceived cold when compared to "best management" alone. This standardized maritime pine bark extract is also linked to reduced use of over-the-counter products to manage symptoms in cases of colds lasting longer than 4 days (91962). However, the validity of these findings is limited by the unblinded, non-randomized nature of the study.
• Dental plaque. It is unclear if chewing gum containing maritime pine bark extract can reduce dental plaque. Details: A small clinical study shows that chewing a minimum of six pieces of gum containing a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 5 mg daily for 14 days reduces gingival bleeding by 55% and prevents an increase in gingival plaque when compared with a control sugar-free gum (50857).
• Diabetes. Small clinical studies suggest that oral maritime pine bark extract may modestly improve glycemic control in patients with type 2 diabetes. Details: Three small clinical studies in patients with type 2 diabetes show that taking a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 50-200 mg daily for 3-12 weeks modestly decreases blood glucose and glycated hemoglobin (HbA1C) levels when compared with placebo (15521,15522,50908). Another small clinical trial in patients with type 2 diabetes and microalbuminuria shows that taking a different standardized maritime pine bark extract (Oligopin, DRT Group) 100 mg daily for 8 weeks reduces HbA1c by around 1%, but does not reduce fasting blood glucose, when compared with placebo (105781).
• Diabetic foot ulcers. It is unclear if oral or topical maritime pine bark extract is beneficial for diabetic foot ulcers. Details: A small clinical study in patients with diabetic foot ulcers shows that taking a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 150 mg daily orally as well as applying the extract topically 100 mg daily heals ulcers in 89% of subjects compared with 61% of control subjects. Using oral or topical maritime pine bark extract alone seems to result in complete ulcer healing in about 85% of subjects (50896).
• Diabetic microangiopathy. It is unclear if oral maritime pine bark extract is beneficial in patients with diabetic microangiopathy. Details: A small, unblinded clinical study in patients with diabetic microangiopathy, symptoms of neuropathy, and edema in the absence of severe cardiovascular disease shows that taking a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 50 mg three times daily for 4 weeks improves microcirculation (measured by laser Doppler flowmetry) and symptoms when compared with no treatment (15523).
• Diabetic retinopathy. It is unclear if oral maritime pine bark extract is beneficial in patients with diabetic retinopathy. Details: A small, unblinded clinical study in patients with retinopathy due to various causes, including diabetes, atherosclerosis, or central venous thrombosis, shows that taking a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 50 mg three times daily for 2 months may slow or prevent further deterioration of retinal function when compared with no treatment (2536).
• Dry mouth. It is unclear if oral maritime pine bark extract is beneficial in patients with dry mouth. Details: Two small observational studies in otherwise healthy adults or patients with diabetes suggest that adding a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) for 2 weeks along with standard saliva supplements is associated with improvement in patient-reported mouth dryness, salivary flow, and the number of small mucosal breaks when compared with saliva supplements alone. One study dosed maritime pine bark extract 150 mg orally daily and the other used a spray formulation dosed 10 mg six times daily (103612,112714). However, the validity of these findings is limited by the unblinded, non-randomized nature of the studies.
• Dysmenorrhea. It is unclear if oral maritime pine bark extract is beneficial in patients with dysmenorrhea. Details: Two small clinical studies in patients with dysmenorrhea show that taking a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 30-60 daily for up to 3 menstrual cycles reduces pain when compared to baseline (15424,50904). The validity of this finding is limited by the lack of a comparator group.
• Erectile dysfunction (ED). Small clinical studies suggest that oral maritime pine bark extract, taken alone or in combination with L-arginine, may modestly improve sexual function in patients with ED. Details: Several small clinical studies in adults with ED show that taking a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) at a dose of 120 mg daily for 3 months, either alone (12012) or in combination with L-arginine (10416,32149,50924), might improve sexual function when compared with placebo or baseline measurements. It seems to take up to 3 months of treatment for significant improvement. Similarly, a meta-analysis of 2 small clinical studies in males with mild to moderate ED shows that taking maritime pine 80 mg with L- arginine daily for 1-6 months improves International Index of Erectile Dysfunction scores by 9 points when compared with control (112715). It is unclear if this effect is from maritime pine, L-arginine, or the combination.
• Exercise-induced muscle soreness. Oral maritime pine bark extract has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small clinical study in non-professional athletes shows that taking a combination product (PycnoRacer, Kobayashi Pharmaceutical Company) containing maritime pine extract 15 mg, L-leucine 0.6 grams, L-arginine 0.3 grams, L-isoleucine 0.3 grams, and L-valine 0.3 grams four times daily for 3 weeks during training improves subjective scores for muscle pain and cramps when compared with water plus Gatorade (103613). It is unclear if these benefits are due to maritime pine, other ingredients, or the combination.
• Glaucoma. Oral maritime pine has only been evaluated in combination with other ingredients; its effects when used alone is unclear. Details: One small, unblinded clinical trial in Japanese patients with open-angle glaucoma shows that taking a specific product (Sante Glagenox, Saten Pharmaceutical Co. Ltd.) containing maritime pine extract 40 mg and bilberry fruit extract 90 mg daily for 4 weeks reduces intraocular pressure by 8.7% when compared to baseline (104192). The validity of this finding is limited by the lack of a comparator group.
• Heart failure. Oral maritime pine bark extract has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small observational study in patients with mild to moderate heart failure has found that taking a specific combination product (PycnoQ10, Natural Health Science Inc.) containing a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) and coenzyme Q10 for 12 weeks is associated with improved exercise capacity and heart function (44178). It is unclear if these findings are due to maritime pine, coenzyme Q10, or the combination.
• Hemorrhoids. It is unclear if oral or topical maritime pine bark extract is beneficial in patients with hemorrhoids. Details: A small clinical study in patients with acute hemorrhoidal episodes shows that taking a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 150-300 mg daily orally, alone or in combination with a cream containing 0.5% standardized maritime pine bark extract (Pycnogenol, Horphag Research) for 7 days, improves both quality of life and hemorrhoidal symptoms when compared with placebo tablets/cream (50912). Additionally, an observational registry study in postpartum adults with internal or external hemorrhoids found that taking this same extract of maritime pine bark 150 mg daily for 6 months, in conjunction with standard hemorrhoid care, is associated with improved symptoms, including thrombosis, pain, swelling, and bleeding, when compared to standard care alone (97416). However, the validity of these findings is limited by the unblinded, non-randomized nature of the study.
• Hypertension. It is unclear if oral maritime pine bark reduces blood pressure; the available research is conflicting. Details: A very small clinical study in patients with mild hypertension (systolic 140-159 mm Hg; diastolic 90-99 mm Hg) shows that taking a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 200 mg daily for 8 weeks may modestly reduce systolic, but not diastolic, blood pressure when compared with placebo (10214). Another very small study in hypertensive patients treated with ramipril, taking this same standardized maritime pine bark extract 50 mg three times daily for 6 months, appears to further reduce diastolic, but not systolic, blood pressure (50913). Conflicting results have been reported with other maritime pine products. A small clinical study in adults with untreated, mild hypertension shows that taking a different standardized extract of maritime pine (Oligopin, DRT Group), 75 mg twice daily for 5 weeks, does not lower systolic or diastolic blood pressure when compared with placebo (97407). Also, a small clinical study in obese patients with prehypertension or hypertension shows that taking a different maritime pine bark extract (Toyo-FVG, Toyo Bio-Pharma) 200 mg daily for 12 weeks does not lower systolic or diastolic blood pressure when compared with placebo (50919). Results of meta-analyses are also contradictory. An analysis of 7 clinical trials using maritime pine bark extract 90-200 mg daily for 2-24 weeks shows no significant effect overall on systolic or diastolic blood pressure, mean arterial pressure, or pulse pressure (103609). However, an analysis of 12 trials using doses of 60-200 mg daily for 4-24 weeks shows a mean reduction of about 3 mmHg in systolic blood pressure, and about 2 mmHg in diastolic blood pressure. There was high heterogeneity between the studies, and the effect on diastolic blood pressure was only seen with a treatment duration of at least 12 weeks (103610).
• Idiopathic interstitial pneumonia. Oral maritime pine bark extract has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small observational registry study in males less than 65 years old with idiopathic interstitial pneumonia has found that taking a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 50 mg three times daily in combination with gotu kola (Centellicum; Horphag Research) 225 mg three times daily for 8 months is associated with a modest improvement in Karnofsky Performance Scale scores and a reduction in fatigue when compared with pirfenidone (108862). However, the validity of these findings is limited by the unblinded, non-randomized nature of the study.
• Irritable bowel syndrome (IBS). It is unclear if oral maritime pine bark extract is beneficial in patients with IBS. Details: An observational registry study in adults with idiopathic IBS found that taking a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 150 mg daily for 4 weeks, in conjunction with standard treatment, is associated with reduced abdominal pain, cramps, and the use of medical care and rescue medications when compared to standard treatment alone. In both groups, standard treatment included specific nutritional recommendations and Buscopan Compositum, hyoscine-N-butylbromide, or acetaminophen for pain relief (97402). However, the validity of these findings is limited by the unblinded, non-randomized nature of the study.
• Jet lag. It is unclear if oral maritime pine bark extract can prevent or treat jet leg. Details: An observational registry study found that taking a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 150 mg daily for up to 10 days, starting 3 days before a plane flight, is associated with reduced signs and symptoms of jet lag when compared to control (97437). Additionally, a small clinical study shows that taking this extract 50 mg three times daily for 7 days, starting 2 days before a plane flight, reduces jet lag symptoms and the average duration of symptoms by a little over 1 day when compared with placebo (97412).
• Leg cramps. It is unclear if oral maritime pine bark extract is beneficial for leg cramps. Details: A small clinical study in patients experiencing at least 4 episodes of leg cramps per week associated with athletic activity, venous insufficiency, or an unknown cause shows that taking a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 200 mg daily for 4 weeks may decrease the incidence of leg cramps when compared to baseline (15524). The validity of this finding is limited by the lack of a comparator group.
• Male infertility. Although there has been interest in using oral maritime pine for male infertility, there is insufficient reliable information about the clinical effects of maritime pine for this purpose.
• Melasma. It is unclear if oral maritime pine bark extract is beneficial for melasma. Details: A small clinical study in females with melasma shows that taking a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 75 mg twice daily for 60 days, along with topical application of sunscreen during the day and a triple cream containing hydroquinone, tretinoin, and fluocinolone at night, improves scores related to melasma severity and aesthetics, but not quality of life, when compared with placebo plus sunscreen and triple cream (105782).
• Meniere disease. It is unclear if oral maritime pine bark extract is beneficial in patients with Meniere disease. Details: Observational registry research in patients with Meniere disease found that taking a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 150 mg daily along with standard treatment is associated with a greater reduction in the severity of tinnitus and the number of work-days lost when compared with standard treatment alone. After 6 months of treatment, about 87% of patients taking maritime pine bark were asymptomatic, compared to about 35% of patients receiving standard treatment alone (97413). However, the validity of these findings is limited by the unblinded, non-randomized nature of the study.
• Menopausal symptoms. Small clinical studies suggest that oral maritime pine bark extract might improve some menopausal symptoms. Details: Several small clinical studies in patients with menopausal symptoms shows that taking a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 60-200 mg daily for 2-6 months modestly reduces perimenopausal symptoms, including tiredness, headache, depression and anxiety, sleep disturbances, vaginal dryness, hot flashes, and loss of memory, when compared with placebo or control (14899,50927,50945).
• Metabolic syndrome. It is unclear if oral maritime pine bark extract is beneficial in patients with metabolic syndrome. Details: A small clinical study in patients with metabolic syndrome shows that taking a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 50 mg three times daily for 6 months lowers triglyceride levels by 46 mg/dL, increases high-density lipoprotein (HDL) cholesterol levels by about 10 mg/dL, reduces fasting plasma glucose by 18 mg/dL, and lowers systolic and diastolic blood pressure by 7 mmHg and 5 mmHg, respectively, when compared to baseline. The validity of these findings is limited by the lack of statistical comparison to a control group. Taking the maritime pine bark extract was also associated with a reduction in the percentage of patients presenting with five risk factors of metabolic syndrome (91960).
• Oral mucositis. It is unclear if topical maritime pine bark extract is beneficial in children with chemotherapy-related oral mucositis. Details: A small clinical study in children 6-15 years of age with chemotherapy-related oral mucositis shows that application of a solution containing a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 1 mg/kg in three divided doses daily for one week promotes complete healing in 58% of patients and improved healing in 38% of patients. This improvement was significantly greater than treatment with glycerine solution and similar to treatment with vitamin E solution (91964).
• Osteopenia. It is unclear if maritime pine bark extract is beneficial in patients with osteopenia. Details: A small clinical study in postmenopausal adults with osteopenia shows that taking a standardized extract of maritime pine bark (Oligopin, DRT Group) 150 mg daily for 12 weeks improves markers of bone turnover when compared with placebo (105783). It is unknown if maritime pine bark extract improves bone mineral density or reduces the risk of fractures in patients with osteopenia.
• Parkinson disease. It is unclear if oral maritime pine bark extract is beneficial in patients with Parkinson disease. Details: Two small observational studies in adults with mild to moderate Parkinson disease suggest that taking a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 150 mg daily for 4 or 8 weeks in conjunction with carbidopa/levodopa therapy is associated with a reduction in scores for tremor, bradykinesia, and rigidity when compared with carbidopa/levodopa therapy alone. Maritime pine is also associated with an increase in the Karnofsky Performance Status Scale score from approximately 75 (cares for self, unable to carry on normal activity or do active work) to approximately 85 (normal activity with effort, some signs or symptoms of disease), compared with little to no change from a score of around 75 in the control group (103614,112716).
• Pregnancy-related pain. It is unclear if oral maritime pine bark extract is beneficial for reducing pain during the third trimester of pregnancy. Details: A small clinical study in patients in the third trimester of pregnancy shows that taking a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 30 mg daily modestly reduces lower back pain, hip joint pain, pelvic pain, and pain due to varicose veins or calf cramps when compared with a control group (15423).
• Psoriasis. It is unclear if oral maritime pine bark extract is beneficial in patients with psoriasis. Details: An observational registry study in adults with moderate to severe plaque psoriasis found that taking a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 150 mg daily for 12 weeks along with standard treatment is associated with improved quality of life, increased water and moisture content of the skin, reduced plaque severity and total affected body area, and reduced use of corticosteroids when compared with standard treatment alone (97417). However, the validity of these findings is limited by the unblinded, non-randomized nature of the study.
• Raynaud syndrome. It is unclear if oral maritime pine bark extract is beneficial in patients with Raynaud syndrome. Details: A small clinical study in females with mild, primary Raynaud syndrome shows that taking a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 50 mg twice daily for 4 weeks decreases coldness, burning pain, paresthesias, skin color changes, and low temperature areas of the hands when compared with lifestyle changes alone. The lowest finger temperature increased by 30% in those taking this product, compared with 13% in those implementing lifestyle changes alone (103615).
• Restless legs syndrome (RLS). It is unclear if oral maritime pine is beneficial for RLS. Details: A small observational study in adults with RLS suggests that taking maritime pine bark extract (Pycnogenol, Horphag Research) 150 mg daily along with standard management (i.e., regular sleep, exercise, vitamin C, B vitamins, proper footwear, and instruction on diet and posture) improves self-reported symptoms associated with RLS when compared to baseline. Maritime pine bark may also be associated with less analgesic use compared with standard management alone (112717). However, the interpretation of these findings, other than analgesic use, is limited by lack of a statistical comparison to the other study group.
• Sarcopenia. It is unclear if oral maritime pine bark extract is beneficial in patients with sarcopenia. Details: Observational registry research in adults over 70 years of age with signs of muscle loss has found that taking a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 150 mg daily along with strength training for 2 months improves hand grip strength, walking distance, total weight lifted, number of steps climbed, and general fitness scores when compared with strength training alone (97404). However, the validity of these findings is limited by the unblinded, non-randomized nature of the study.
• Sexual dysfunction. Oral maritime pine bark extract has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small clinical study in females with sexual dysfunction shows that taking a specific combination tablet (Lady Prelox, Horphag Research) containing a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 20 mg, L-arginine 200 mg, L-citrulline 200 mg, and a standardized rose hip extract (Rosvita) orally 50 mg daily for 8 weeks, in combination with a management program consisting of lifestyle, diet, exercise, and stress control changes, improves overall sexual function when compared with the management program alone (91963). Taking the same product in a dose of 2 tablets twice daily for 8 weeks, in addition to the lifestyle management program, improves vaginal dryness in pre- and post-menopausal patients when compared with lifestyle management alone (103611). The effect of maritime pine alone on sexual dysfunction is unclear.
• Sjogren syndrome. It is unclear if oral maritime pine bark extract is beneficial in patients with Sjogren syndrome. Details: A very small observational study in patients with Sjogren syndrome found that taking a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 150 mg daily in addition to standard therapy is associated with a reduction in dry eye, dry mouth, and the need for corticosteroids when compared with standard therapy alone (100360).
• Systemic lupus erythematosus (SLE). It is unclear if oral maritime pine bark extract is beneficial in patients with SLE. Details: A very small clinical study in adults with SLE shows that taking a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 120 mg daily for 30 days, followed by 60 mg daily for 30 days, modestly reduces symptoms of SLE in some patients when compared with control (50851).
• Traumatic brain injury (TBI). It is unclear if oral maritime pine bark extract is beneficial in patients with TBI. Details: A clinical study in patients admitted to the intensive care unit with TBI shows that administering a standardized maritime pine bark extract (Oligopin, DRT Group) 50 mg three times daily with enteral nutrition for 10 days improves scores on the sequential organ failure assessment (SOFA) and APACHE II [Acute Physiology and Chronic Health Evaluation II], as well as nutritional status, when compared with placebo. At day 28, survival rate was 86% in the treatment group, compared to 71% in the placebo group; however, this difference was not statistically significant (108861).
• Urinary tract infections (UTIs). It is unclear if oral maritime pine bark extract is beneficial in patients with recurrent UTIs or interstitial cystitis. Details: An observational registry study in adults aged 30-40 years with a recent history of recurrent UTIs has found that taking a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 150 mg daily for 2 months is associated with a normal urinalysis in 92% of patients, compared with 68% of those who received no supplementation (108860). Another observational registry study in patients with recurrent UTIs or interstitial cystitis has found that taking this same dose for 2 months is associated with a normal urinalysis in 100% of patients, compared with 35% of patients who took oral cranberry extract 400 mg daily and 36% of those who received no treatment (108859). However, the validity of these findings is limited by the unblinded, non-randomized nature of these studies.
• Varicose veins. It is unclear if oral maritime pine bark extract is beneficial in patients with varicose veins. Details: Observational registry research in postpartum adults has found that taking a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 50 mg daily for 6 months, in addition to using below-knee compression stockings, is associated with reduced edema, leg cramps, total number of varicose veins, and number of visible spider vein clusters when compared with compression stockings alone (97403). However, the validity of these findings is limited by the unblinded, non-randomized nature of the study.
• Venous thromboembolism (VTE). While some conflicting evidence exists, low-quality clinical research suggests that oral maritime pine bark extract might prevent superficial thrombosis during flights and reduce the incidence of post-thrombotic syndrome (PTS) in patients with a history of deep vein thrombosis (DVT). Details: Observational registry research has found that a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 150 mg daily for 10 days is not associated with reduced occurrence of DVT, a type of VTE, when compared with compression stockings or control (97437). However, an older clinical study in patients at moderate or high risk for thrombotic events shows that taking a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 200 mg 2-3 hours before a flight seems to reduce superficial thrombosis, but not DVT risk, when compared with placebo (50874). Some observational research also has also found that taking standardized maritime pine bark extract (Pycnogenol, Horphag Research) is associated with reduced post-thrombotic syndrome (PTS) and recurrent DVT (100355). Also, some clinical research shows that taking standardized extract of maritime pine bark (Pycnogenol, Horphag Research) daily for one year, while wearing or not wearing compression stockings, reduces the incidence of PTS in patients with a single prior episode of DVT (50925). Maritime bark has also been studied in combination with other natural products. There is some evidence that taking a specific combination product (Flite Tabs, Aidan Products) before a flight and then again 6 hours later might decrease the risk of DVT during long-haul plane flights in high-risk patients. The product combines a blend of 150 mg of standardized extract of maritime pine bark (Pycnogenol, Horphag Research) plus nattokinase (12075).
• Wrinkled skin. It is unclear if oral maritime pine bark extract can reduce wrinkles or improve skin health in people with significant sun exposure. Details: A small crossover study in Chinese adults working outdoors shows that taking a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 50 mg twice daily for 12 weeks improves skin hydration and reduces transepidermal water loss and skin darkening when compared with placebo (105784). More evidence is needed to rate maritime pine for these uses.

(Read more about MARITIME PINE)

LIKELY EFFECTIVE

• Dyslipidemia. Niacin prescription products, in doses of 500 mg or greater, are FDA-approved for primary hyperlipidemia and mixed dyslipidemia. Niacin dietary supplements are generally available in lower doses and have not been shown to improve lipid levels. Details: Prescription niacin is not routinely recommended as second-line therapy for patients who primarily need to decrease low-density lipoprotein (LDL) cholesterol. This is due to results from clinical trials showing no effect on cardiovascular related events or mortality (93346,93354,96208,96211,97308,97477,97336). However, niacin might be considered for patients with mixed hyperlipidemia or patients who need to increase high-density lipoprotein (HDL) cholesterol and lower triglycerides. Niacin might also be effective for isolated hypoalphalipoproteinemia (4817). The most pronounced increases in HDL and decreases in triglycerides occur at 1-1.5 grams daily, and the greatest LDL reduction occurs at 2-3 grams daily. Niacin reduces LDL cholesterol by up to 25%, compared with up to a 55% reduction with statins. High-dose niacin can also decrease triglycerides by 20% to 50%, increase HDL by 13% to 35%, decrease apolipoprotein B levels by 2% to 20%, and decrease lipoprotein(a) levels by 23% (4818,4886,4887,4888,4889,4890,12033,25567,93347,96213). The effects of higher dose extended-release niacin on LDL cholesterol and triglycerides appear to be greater in females than males (25565). Experts recommend maximizing statins first because they have the best evidence for improving cardiovascular outcomes (97477,97336,97337). However, if patients cannot reach their LDL goal with a statin alone or if they cannot tolerate a statin, niacin might be combined with other cholesterol-lowering drugs when diet and single-drug therapy are not adequately effective (8545,25566,93351,94191,97337). Adding low-dose niacin, 50 mg daily, to statin therapy has no additional benefit on lipid levels (8546). Population research in adults without dyslipidemia has also found that higher dietary intake of niacin for 3-10 years is associated with a 29% lower risk of developing dyslipidemia when compared with low dietary niacin intake (110493).
• Pellagra. Oral niacin is FDA-approved for the prevention and treatment of pellagra. Details: Population research has found that low consumption of niacin is associated with an increased risk of developing pellagra (25903). Taking niacin 500-1000 mg daily can resolve symptoms of pellagra within a week of treatment initiation (25904). However, niacinamide is sometimes preferred for this indication because it lacks the vasodilating effects of niacin (15,6243).

POSSIBLY EFFECTIVE

• HIV/AIDS-related dyslipidemia. Oral niacin seems to improve lipid levels in patients with dyslipidemia due to HIV/AIDs. Details: Small clinical trials in HIV patients with dyslipidemia associated with antiretroviral therapy shows that taking extended-release niacin (Niaspan, Abbott Laboratories) titrated up to 2 grams daily for 14-48 weeks improves total cholesterol, high-density lipoprotein (HDL) cholesterol, and triglyceride levels when compared to baseline (25570,25902). Other preliminary clinical research in this population shows that taking extended-release niacin (Niaspan, Abbott Laboratories) titrated to 2 grams daily for up to 2 years improves HDL cholesterol levels, but not total cholesterol or triglyceride levels, when compared with no treatment (25569).
• Metabolic syndrome. Oral niacin seems to improve lipid levels in patients with metabolic syndrome. Details: Clinical research shows that taking niacin (Niaspan, Abbott Laboratories) 2 grams daily orally for 16 weeks reduces triglyceride levels by 39 mg/dL and increases high-density lipoprotein (HDL) cholesterol by 5 mg/dL when compared to baseline in patients with metabolic syndrome. These improvements are significant when compared with placebo and are further increased when niacin is taken along with prescription omega-3 ethyl esters (Lovaza, GlaxoSmithKline Pharmaceuticals) 4 grams daily orally (93353). However, niacin does not seem to improve postprandial glucose levels in patients with metabolic syndrome (97333).

INEFFECTIVE

• Cardiovascular disease (CVD). Oral niacin does not seem to reduce cardiovascular-related events in patients with or without CVD. Details: Overall, niacin is not recommended for primary or secondary prevention of CVD. Most clinical trials and meta-analyses conducted prior to 2011 showed a reduction in cardiovascular-related events, cardiovascular-related mortality, and all-cause mortality in patients taking niacin alone or in combination with a statin or clofibrate for primary or secondary prevention of CVD (4847,7388,25095,25911,25912,93349). However, recent meta-analyses of these studies and additional moderate-to-high quality research conducted in over 39,000 patients show no effect of niacin on cardiovascular-related events, cardiovascular-related mortality, or overall mortality (93346,93354,96208,96211,97308). Additionally, one meta-analysis shows that patients taking niacin are twice as likely to report side effects when compared with placebo (96211).

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Alzheimer disease. It is unclear if oral niacin is beneficial for reducing Alzheimer disease risk. Details: Observational research has found that consuming higher amounts of niacin (17-45 mg daily) from food and supplements is associated with a slower cognitive decline and a lower risk of developing Alzheimer disease when compared with people who consume less niacin (14 mg daily) (12077). It is not known if the risk of Alzheimer disease is reduced by taking a stand-alone niacin supplement.
• Atherosclerosis. It is unclear if oral niacin prevents atherosclerosis progression. Details: Preliminary clinical studies show that taking niacin orally, in combination with colestipol for up to 2 years, might modestly reduce progression of atherosclerosis as measured by coronary lesions and carotid arterial intima-media thickness in high-risk males with existing coronary atherosclerosis (25906,25909,25910). However, niacin does not seem to be better than statins. One clinical study in adults with atherosclerosis and peripheral arterial disease shows that taking extended-release niacin 1500 mg, simvastatin 40 mg, and ezetimibe 10 mg daily for 2 years does not reduce atherosclerosis of the superficial femoral artery when compared with simvastatin alone (96208). Niacin has also not been shown to prevent cardiovascular events or mortality (93346,93354,96208,96211,97308).
• Athletic performance. It is unclear if oral niacin improves athletic performance. Details: Preliminary clinical research in untrained adult males shows that taking niacin 1000 mg orally once before a cycling test does not improve power, respiratory exchange ratio, or time to exhaustion when compared with placebo. In addition, these measures were significantly worse when compared with taking caffeine 5 mg/kg orally as a single dose (107942). Clinical research in untrained males also shows that taking a supplement containing niacin 40 mg, caffeine 400 mg, capsicum extract 66.7 mg, and black pepper extract 10 mg prior to exercising does not improve strength, time to exhaustion, or maximal oxygen consumption when compared with placebo (37873).
• Attention deficit-hyperactivity disorder (ADHD). Although there is interest in using oral niacin for ADHD, there is insufficient reliable information about the clinical effects of niacin for this condition.
• Cancer. It is unclear if dietary niacin is beneficial for cancer. Details: Population research in adults with cancer has found that high dietary niacin intake is associated with 49% and 27% lower risk of cancer-related mortality and all-cause mortality when compared with low dietary niacin intake. The same study also found that taking niacin supplements is associated with a lower risk of cancer-related mortality, but not all-cause mortality when compared with not taking niacin supplements (110496).
• Cataracts. It is unclear if oral niacin is beneficial for preventing cataracts. Details: Population research has found that high dietary intake of niacin is associated with a reduced risk of nuclear cataracts (6378). However, there is no reliable evidence that niacin supplements reduce the risk of cataracts.
• Cholera. It is unclear if oral niacin is beneficial for cholera. Details: One small clinical study in adults with severe cholera shows that taking 1-2 grams niacin orally reduces fluid loss in the stool by 31% to 47% in the first 16 hours when compared with control. The 2 gram dose seemed to result in a greater reduction in fluid loss than the 1 gram dose (4868).
• Erectile dysfunction (ED). It is unclear if oral niacin is beneficial in patients with ED and dyslipidemia. Details: Clinical research in patients with erectile dysfunction and dyslipidemia shows that taking extended-release niacin (Niaspan, Abbott Laboratories) titrated to 1.5 grams nightly for a total of 12 weeks significantly improves penetration frequency and the maintenance of an erection after penetration when compared to baseline (25913). The validity of this finding is limited by the lack of a comparator group.
• Glaucoma. It is unclear if oral niacin is beneficial for preventing or treating glaucoma. Details: Population research has found that higher dietary intake of niacin is associated with a lower odds of having glaucoma. However, this association was not consistently present when adjusting for confounders. The effects of niacin supplementation on glaucoma have not been evaluated (107942).
• Hyperphosphatemia. It is unclear if oral niacin is beneficial for preventing high levels of phosphorus in the blood. Details: Preliminary clinical research in patients on maintenance dialysis who are no longer using phosphate binders shows that taking niacin 375-750 mg daily for 8 weeks reduces serum phosphorus levels by 2.1 mg/dL, increases calcium levels by 0.4 mg/dL, and decreases serum alkaline phosphatase when compared with baseline (25914). However, clinical research in hemodialysis patients with inadequate phosphate control despite using standard phosphate-binding therapy shows that taking niacin at the maximum tolerated dose, up to 1000 mg daily, for 12 weeks, does not decrease serum phosphate levels when compared with placebo (93341). It is possible that this latter study was too small to observe between-group differences in changes in serum phosphate levels.
• Hypertension. It is unclear if dietary niacin is beneficial for preventing hypertension. Details: Observational research in Chinese adults found a J-shaped association between dietary niacin intake and development of hypertension, with the lowest risk occurring in those with a daily dietary niacin intake of 14.3-16.7 mg (104934).
• Meniere disease. Although there is interest in using oral niacin for Meniere disease, there is insufficient reliable information about the clinical effects of niacin for this condition.
• Migraine headache. It is unclear if dietary niacin is beneficial for preventing migraine headaches. Details: Population research in adults has found that high dietary intake of niacin is associated with a 28% lower likelihood of having migraine headaches when compared with low dietary intake of niacin (110495). However, the effect of niacin supplementation on migraines has not been studied.
• Motion sickness. Although there is interest in using oral niacin for motion sickness, there is insufficient reliable information about the clinical effects of niacin for this purpose.
• Parkinson disease. It is unclear if oral niacin is beneficial for improving Parkinson disease symptoms. Details: Low-quality clinical research in adults with Parkinson disease shows that taking slow-release niacin 250 mg orally daily for 12 months improves Parkinson disease motor scores and fatigue scores by 17% and 26%, respectively, when compared with baseline (107944). However, higher quality clinical research shows that taking niacin 250 mg orally daily for 6 months does not improve Parkinson disease motor scores when compared with placebo (107943).
• Retinal vein occlusion. It is unclear if oral niacin is beneficial for improving retinal vein occlusion symptoms. Details: A small case series in patients with chronic retinal vein occlusion shows that taking niacin titrated to 500 mg three times daily for 1 year is associated with reduced central macular thickness and improved visual acuity in over 50% of patients when compared with a control group. The addition of prednisolone eye drops does not alter the outcomes of those taking niacin (96212). The validity of this finding is limited due to the retrospective nature of this study.
• Sickle cell disease. It is unclear if oral niacin is beneficial for improving lipid levels in patients with sickle cell disease. Details: A small clinical study in patients with sickle cell disease shows that taking extended-release niacin titrated to 1.5 grams daily for 12 weeks does not improve vascular function or increase high-density lipoprotein (HDL) or apolipoprotein A-I cholesterol levels when compared with placebo (96209).
• Schizophrenia. Although there is interest in using oral niacin for schizophrenia, there is insufficient reliable information about the clinical effects of niacin for this condition.
• Vertigo. Although there is interest in using oral niacin for vertigo, there is insufficient reliable information about the clinical effects of niacin for this condition. More evidence is needed to rate niacin for these uses.

(Read more about NIACIN)

POSSIBLY SAFE ...when used orally and appropriately in medicinal amounts, short-term. Agmatine sulfate has been used with apparent safety at doses up to 2.67 grams daily for up to 2 months and 3.56 grams daily for up to 3 weeks (94736,111144).

PREGNANCY AND LACTATION:
Insufficient reliable information available; avoid using.

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POSSIBLY SAFE ...when used orally and appropriately for up to 3 years (5311,18113,30784,30785,30778). When used topically for up to 8 weeks (111125). ...when used intravenously and appropriately (5308,5309,5310,5311,5312,5313).

PREGNANCY AND LACTATION:
Insufficient reliable information available; avoid using.

(Read more about ALPHA-KETOGLUTARATE (AKG))

POSSIBLY SAFE ...when used orally and appropriately. In clinical trials, L-citrulline has been used with apparent safety for up to 2 months at doses of 1.5-6 grams daily (94954,94956,94961,94962,100974). Doses of up to 15 grams have also been used as single doses or within a 24 hour period (16470,16473).

CHILDREN: POSSIBLY SAFE
when used orally and appropriately. L-citrulline has been used with apparent safety in infants at a dose of 0.17 grams/kg daily (16472). It has also been used in children 6.5-10 years of age at a dose of 7.5 grams daily for 26 weeks (100976). ...when used intravenously and appropriately. An intravenous bolus dose of L-citrulline 150 mg/kg followed by 9 mg/kg/hour for 48 hours has been used safely in children under 6 years of age (16469).

PREGNANCY AND LACTATION:
Insufficient reliable information available; avoid using.

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POSSIBLY SAFE ...when used orally and appropriately. A standardized extract of maritime pine bark (Pycnogenol, Horphag Research) has been safely used in doses of 50-450 mg daily for up to one year (2435,2451,2462,2554,2556,7693,10214,10416,12012,14899) (15424,15521,15522,15523,15524,100359,105782). The same extract has also been used with apparent safety in a dose of 800 mg daily for 16 days (103617). A different standardized extract of maritime pine bark (Oligopin, DRT Group) has been used with apparent safety in doses of up to 150 mg daily for up to 12 weeks (105781,105783). ...when applied topically as a cream or powder. A standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 0.5% cream has been used for up to 7 days (50912). Powder from a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) 100 mg has been applied to the skin daily for up to 6 weeks (50887,50896).

CHILDREN: POSSIBLY SAFE
when used orally and appropriately, short-term. A standardized extract of maritime pine bark (Pycnogenol, Horphag Research), administered in a dose of 1 mg/lb body weight daily, has been safely used in a clinical study of children aged 6-18 years for up to 3 months (13120).

PREGNANCY: POSSIBLY SAFE
when used orally during the third trimester of pregnancy. In one small clinical study, a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) has been used at a dose of 30 mg daily with apparent safety during the third trimester of pregnancy (15423). However, more evidence is needed; use cautiously or avoid using.

LACTATION:
There is insufficient reliable information available regarding the safety of maritime pine when used during lactation; avoid using.

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LIKELY SAFE ...when niacin is taken in food or as a supplement in amounts below the tolerable upper intake level (UL) of 30 mg daily for adults 18 years of age and 35 mg daily for adults 19 years and older (6243). ...when prescription products are used orally and appropriately in doses of up to 2 grams daily (12033). CHILDREN:

LIKELY SAFE ...when used orally in amounts that do not exceed the tolerable upper intake level (UL). The ULs of niacin for children are: 1-3 years of age, 10 mg daily; 4-8 years of age, 15 mg daily; 9-13 years of age, 20 mg daily; 14-18 years of age, 30 mg daily (6243).

PREGNANCY AND LACTATION: LIKELY SAFE
when used orally in amounts that do not exceed the tolerable upper intake level (UL). The UL of niacin during pregnancy and lactation is 30 mg daily for 14-18 years of age and 35 mg daily for 19 years and older (6243). There is insufficient reliable information available about the safety of larger oral doses of niacin during pregnancy or lactation; avoid using.

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ANTIDIABETES DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, agmatine might increase the risk of hypoglycemia when taken with antidiabetes drugs.  Details Animal and in vitro research suggest that agmatine has mild hypoglycemic effects (94734).

ANTIHYPERTENSIVE DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, agmatine might increase the risk of hypotension when taken with antihypertensive drugs.  Details Animal research suggests that agmatine can modestly decrease heart rate and blood pressure (94734).

(Read more about AGMATINE)

(Read more about ALPHA-KETOGLUTARATE (AKG))

ANTIHYPERTENSIVE DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Theoretically, concomitant use of L-citrulline with antihypertensive drugs might have additive effects and increase the chance of hypotension.  Details L-citrulline is converted to L-arginine, which can increase nitric oxide and cause vasodilation (7822,16460,16461). However, a meta-analysis of 5 small clinical studies suggests that taking L-citrulline 3-6 grams daily for 1-8 weeks does not lower blood pressure when compared with control (100974).

PHOSPHODIESTERASE-5 INHIBITORS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, concurrent use of phosphodiesterase-5 (PDE-5) inhibitors and L-citrulline might result in additive vasodilation.  Details L-citrulline is converted to L-arginine, which can increase nitric oxide and cause vasodilation (7822,16460,16461). Theoretically, taking L-arginine with PDE-5 inhibitors might have additive vasodilatory and hypotensive effects. However, in studies evaluating the combined use of L-arginine and sildenafil for erectile dysfunction, hypotension was not reported (105065).

(Read more about L-CITRULLINE)

ANTICOAGULANT/ANTIPLATELET DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, maritime pine bark extract might increase the risk of bleeding when used with antiplatelet or anticoagulant drugs.  Details Clinical research suggests that maritime pine bark extract inhibits platelet aggregation (3283,50844,50942). However, the clinical significance of this effect is unclear.

ANTIDIABETES DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Theoretically, maritime pine bark extract might increase the risk of hypoglycemia when used with antidiabetes drugs.  Details One clinical study shows that maritime pine bark extract decreases blood sugar in patients with diabetes being treated with antidiabetes agents (15522). Monitor blood glucose levels closely. Dose adjustments might be necessary.

IMMUNOSUPPRESSANTS Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, maritime pine bark extract might decrease the effectiveness of immunosuppressant therapy.  Details In vitro and animal research suggests that maritime pine bark extract has immunostimulant activity (2435,2636). This effect has not been reported in humans.

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ALCOHOL (Ethanol) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = D Concomitant use of alcohol and niacin might increase the risk of flushing and hepatotoxicity.  Details Alcohol can exacerbate the flushing and pruritus associated with niacin (4458,11689). Large doses of niacin might also exacerbate liver dysfunction associated with chronic alcohol use. A case report describes delirium and lactic acidosis in a patient taking niacin 3 grams daily who ingested 1 liter of wine (14510). Advise patients to avoid large amounts of alcohol while taking niacin.

ALLOPURINOL (Zyloprim) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = C Theoretically, niacin might antagonize the therapeutic effects of uricosurics such as allopurinol.  Details Large doses of niacin can reduce urinary excretion of uric acid, potentially resulting in hyperuricemia (4860,4863,12033). Doses of uricosurics such as allopurinol might need to be increased to maintain control of gout in patients who start taking niacin (4458). People who have frequent attacks of gout despite uricosuric therapy should avoid niacin (4863).

ANTICOAGULANT/ANTIPLATELET DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, niacin may have additive effects when used with anticoagulant or antiplatelet drugs.  Details Several cases of clotting factor synthesis deficiency and coagulopathy have been reported in patients taking sustained-release niacin (25915). Also, thrombocytopenia has been reported in patients treated with niacin or niacin plus lovastatin (25916).

ANTIDIABETES DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = B Niacin can increase blood glucose levels and may diminish the effects of antidiabetes drugs.  Details Niacin impairs glucose tolerance in a dose-dependent manner, probably by causing or aggravating insulin resistance and increasing hepatic production of glucose (4860,4863,11692,11693). In diabetes patients, niacin 4.5 grams daily for 5 weeks can increase plasma glucose by an average of 16% and glycated hemoglobin (HbA1c) by 21% (4860). However, lower doses of 1.5 grams daily or less appear to have minimal effects on blood glucose (12033). In some patients, glucose levels increase when niacin is started, but then return to baseline when a stable dose is reached (12033,93344). Up to 35% of patients with diabetes may need adjustments in hypoglycemic therapy when niacin is added (4458,4860,4863,11689,12033).

ANTIHYPERTENSIVE DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Theoretically, niacin may increase the risk of hypotension when used with antihypertensive drugs.  Details The vasodilating effects of niacin can cause hypotension (4863,12033,93341). Furthermore, some clinical evidence suggests that a one-hour infusion of niacin can reduce systolic, diastolic, and mean blood pressure in hypertensive patients. This effect is not observed in normotensive patients (25917).

ASPIRIN Interaction Rating = Minor Be watchful with this combination. Severity = Insignificant •  Occurrence = Likely •  Level of Evidence = B Large doses of aspirin might alter the clearance of niacin.  Details Aspirin is often used with niacin to reduce niacin-induced flushing (4458,11689). Doses of 80-975 mg aspirin have been used, but 325 mg appears to be optimal (4458,4852,4853,11689). Aspirin also seems to reduce the clearance of niacin by competing for glycine conjugation. Taking aspirin 1 gram seems to reduce niacin clearance by 45% (14524). This is probably a dose-related effect and not clinically significant with the more common aspirin dose of 325 mg (11689,14524).

BILE ACID SEQUESTRANTS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Bile acid sequestrants can bind niacin and decrease absorption. Separate administration by 4-6 hours to avoid an interaction.  Details In vitro studies show that colestipol (Colestid) binds about 98% of available niacin and cholestyramine (Questran) binds 10% to 30% (14511).

GEMFIBROZIL (Lopid) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, concomitant use of niacin and gemfibrozil might increase the risk of myopathy in some patients.  Details A case of myopathy from concomitant use of niacin and gemfibrozil has been reported (25920). Niacin alone has also been associated with cases of myopathy (26100,26111). Using gemfibrozil with niacin might further increase the risk of developing myopathy.

HEPATOTOXIC DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, concomitant use of niacin and hepatotoxic drugs might increase the risk of hepatotoxicity.  Details Niacin has been associated with cases of liver toxicity, especially when used in pharmacologic doses (4863,11689,11691,25929,25930,25931). Sustained-release niacin preparations appear to be associated with a higher risk of hepatotoxicity than immediate-release niacin (11691,25930,25931,93342).

HMG-CoA REDUCTASE INHIBITORS ("Statins") Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, concomitant use of niacin and statins might increase the risk of myopathy and rhabdomyolysis in some patients.  Details Some case reports have raised concerns that niacin might increase the risk of myopathy and rhabdomyolysis when combined with statins (14508,25918). However, a significantly increased risk of myopathy has not been demonstrated in clinical trials, including those using an FDA-approved combination of lovastatin and niacin (Advicor) (7388,11689,12033,14509).

PROBENECID (Benemid) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = C Theoretically, niacin might antagonize the therapeutic effects of uricosurics such as probenecid.  Details Large doses of niacin reduce urinary excretion of uric acid, potentially causing hyperuricemia (4863,12033). Doses of uricosurics such as probenecid might need to be increased to maintain control of gout in patients who start taking niacin (4458). People who have frequent attacks of gout despite uricosuric therapy should avoid niacin (4863).

SULFINPYRAZONE (Anturane) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = C Theoretically, niacin might antagonize the therapeutic effects of uricosurics such as sulfinpyrazone.  Details Large doses of niacin reduce urinary excretion of uric acid, potentially causing hyperuricemia (4863,12033). Doses of uricosurics such as sulfinpyrazone might need to be increased to maintain control of gout in patients who start taking niacin (4458). People who have frequent attacks of gout despite uricosuric therapy should avoid niacin (4863).

THYROID HORMONE Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = D Theoretically, niacin might antagonize the therapeutic effects of thyroid hormones.  Details Clinical research and case reports suggests that taking niacin can reduce serum levels of thyroxine-binding globulin by up to 25% and moderately reduce levels of thyroxine (T4) (25916,25925,25926,25928). Patients taking thyroid hormone for hypothyroidism might need dose adjustments when using niacin.

TRANSDERMAL NICOTINE (Nicoderm) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, concomitant use of niacin and transdermal nicotine might increase the risk of flushing and dizziness.  Details Niacin and nicotine can both cause flushing and dizziness (496,96211).

(Read more about NIACIN)

General ...Orally, agmatine seems to be well tolerated when used in medicinal amounts, short-term.
Most Common Adverse Effects:
Orally: Diarrhea, dyspepsia, nausea.

Gastrointestinal ...Orally, agmatine has been reported to cause diarrhea, dyspepsia, and nausea in two small clinical studies (94736,94742). Mild-to-moderate diarrhea and nausea were reported in 3 out of 24 patients taking agmatine sulfate 3.56 grams daily. These adverse effects appeared within 2-3 days of therapy and resolved upon treatment discontinuation (94736).

(Read more about AGMATINE)

General ...Orally, topically, and intravenously, alpha-ketoglutarate seems to be well tolerated.

(Read more about ALPHA-KETOGLUTARATE (AKG))

General ...Orally, L-citrulline seems to be generally well tolerated.
Most Common Adverse Effects:
Orally: Gastrointestinal discomfort, heartburn.

Gastrointestinal ...Orally, gastrointestinal intolerance, stomach discomfort, and heartburn have been reported with L-citrulline use (94955,94963,94966).

Genitourinary ...Orally, 2 of 25 patients with pulmonary hypertension reported increased urinary frequency and edema while taking 1 gram of powdered L-citrulline in water daily (94963).

Pulmonary/Respiratory ...Orally, 2 of 25 patients with pulmonary hypertension reported cough while taking 1 gram of powdered L-citrulline in water daily (94963).

(Read more about L-CITRULLINE)

General ...Orally and topically, maritime pine bark extract seems to be well tolerated.
Most Common Adverse Effects:
Orally: Gastrointestinal complaints, dizziness, and vertigo.

Cardiovascular ...A single case of chest pain has been reported for a patient treated with a standardized extract of maritime pine bark (Pycnogenol, Horphag Research). However, the patient had a history of myocardial infarction (50905). Another patient taking the same maritime pine bark extract experienced acute decompensation of heart failure. The patient previously has stable coronary artery disease (50929). It is not clear if either of these adverse effects were directly related to maritime pine bark extract.

Gastrointestinal ...Orally, a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) may cause gastrointestinal problems (15521,15522,17300,50891,50942). Also, mouth ulcer and bad breath have been reported in a single trial (15521).

Neurologic/CNS ...Orally, a standardized extract of maritime pine bark (Pycnogenol, Horphag Research) may cause dizziness and severe vertigo (15521,15522,17300,50904,50933). Also, headache has been reported in a single trial (15521).

(Read more about MARITIME PINE)

General ...Orally, niacin is well tolerated in the amounts found in foods. It is also generally well tolerated in prescription doses when monitored by a healthcare provider.
Most Common Adverse Effects:
Orally: Flushing, gastrointestinal complaints (abdominal pain, constipation, diarrhea, heartburn, nausea, vomiting), and elevated liver enzymes.
Serious Adverse Effects (Rare):
Orally: Hepatotoxicity, myopathy, thrombocytopenia, and vision changes.

Cardiovascular ...Orally, flushing is a common dose-related adverse reaction to niacin. A large meta-analysis of clinical studies shows that up to 70% of patients may experience flushing (96211). Although flushing can occur with doses of niacin as low as 30 mg daily, it is more common with the larger doses used for treatment of dyslipidemia. The flushing reaction is due to prostaglandin-induced blood vessel dilation and can also include symptoms of burning, tingling, urticaria, erythema, pain, and itching of the face, arms, and chest. There may also be increased intracranial blood flow and headache (4889,26089,93341,104933). Onset is highly variable and ranges from within 30 minutes to as long as 6 weeks after the initial dose (6243). Flushing can be minimized via various strategies, including taking doses with meals, slow dose titration, using extended release formulations, pretreating with non-steroidal anti-inflammatory drugs, taking regular-release niacin with meals, or taking the sustained-release product at bedtime (4852,4853,4854,4857,4858,25922,26073,26084). Flushing often diminishes with continued use but can recur when niacin is restarted after missed doses (4863,6243,26081). The vasodilating effects of niacin can also cause hypotension, dizziness, tachycardia, arrhythmias, syncope, and vasovagal attacks, especially in patients who are already taking antihypertensive drugs (4863,12033,93341,110494).
High doses of niacin can raise homocysteine levels. A 17% increase has been reported with 1 gram daily and a 55% increased has been reported with 3 grams daily. Elevated homocysteine levels are an independent risk factor for cardiovascular disease (490); however, the clinical significance of this effect is unknown. A large-scale study (AIM-HIGH) found that patients receiving extended-release niacin (Niaspan) 1500-2000 mg daily with a statin had an over two-fold increased risk of ischemic stroke (1.6%) when compared with those receiving only simvastatin (0.7%). However, when the risk was adjusted for confounding factors, niacin was not found to be associated with increased stroke risk (17627,93354). A meta-analysis of three clinical trials conducted in approximately 29,000 patients showed a higher risk of mortality in patients taking niacin in addition to a statin when compared with a statin alone. However, with a p-value of 0.05 and confidence interval including 1, the validity of this finding remains unclear (97308).

Endocrine ...Orally, niacin can impair glucose tolerance in a dose-dependent manner. Dosages of 3-4 grams daily appear to increase blood glucose in patients with or without diabetes, while dosages of 1.5 grams daily or less have minimal effects (12033). Niacin is thought to impair glucose tolerance by increasing insulin resistance or increasing hepatic output of glucose (4863,11692,11693). In patients with diabetes, niacin 4.5 grams daily for 5 weeks has been associated with an average 16% increase in plasma glucose and 21% increase in glycated hemoglobin (HbA1C) (4860). Up to 35% of patients with diabetes may need to increase the dose or number of hypoglycemic agents when niacin is started (4458,4860,4863,11689,12033). Occasionally, severe hyperglycemia requiring hospitalization can occur (11693). In patients with impaired fasting glucose levels, niacin may also increase fasting blood glucose, and adding colesevelam might attenuate this effect (93343).
Although patients without diabetes seem to only experience small and clinically insignificant increases in glucose (4458), niacin might increase their risk of developing diabetes. A meta-analysis of clinical research involving over 26,000 patients shows that using niacin over 5 years is associated with increased prevalence of new onset type 2 diabetes at a rate of 1 additional case of diabetes for every 43 patients treated with niacin (96207). This finding is limited because the individual trials were not designed to assess diabetes risk and the analysis could not be adjusted for confounding factors like obesity. One small clinical study shows that taking extended-release niacin with ezetimibe/simvastatin does not increase the risk of a new diagnosis of diabetes or need for antidiabetic medication when compared with ezetimibe/simvastatin alone after 16 months (93344). This may indicate that the increased risk of developing diabetes is associated with niacin use for more than 16 months.
Niacin therapy has also been linked with hypothyroidism and its associated alterations in thyroid hormone and binding globulin tests (such as decreased total serum thyroxine, increased triiodothyronine, decreased thyroxine-binding globulin levels, and increased triiodothyronine uptake) (25916,25925,25926,25928).

Gastrointestinal ...Orally, large doses of niacin can cause gastrointestinal disturbances including nausea, vomiting, bloating, heartburn, abdominal pain, anorexia, diarrhea, constipation, and activation of peptic ulcers (4458,4863,12033,26083,93341,96211). These effects may be reduced by taking the drug with meals or antacid, and usually disappear within two weeks of continued therapy (4851,26094). Gastrointestinal effects may be more common with time-release preparations of niacin (11691).

Hematologic ...Orally, sustained-release niacin has been associated with cases of reversible coagulopathy, mild eosinophilia, and decreased platelet counts (4818,25915,26097,93340). Also, there have been reports of patients who developed leukopenia while taking niacin for the treatment of hypercholesterolemia (25916).

Hepatic ...Orally, niacin is associated with elevated liver function tests and jaundice, especially with doses of 3 grams/day or more, and when doses are rapidly increased (4458,4863,6243). The risk of hepatotoxicity appears to be higher with slow-release and extended-release products (4855,4856,4863,6243,11691,12026,12033,93342). Niacin should be discontinued if liver function tests rise to three times the upper limit of normal (4863). There are rare cases of severe hepatotoxicity with fulminant hepatitis and encephalopathy due to niacin (4863,6243,11691). Also, there is at least one case of niacin-induced coagulopathy resulting from liver injury without liver enzyme changes (93340).

Musculoskeletal ...Orally, niacin has been associated with elevated creatine kinase levels (4818,4888). Also, several cases of niacin-induced myopathy have been reported (26100,26111). Concomitant administration of niacin and HMG-CoA reductase inhibitors may increase the risk of myopathy and rhabdomyolysis (14508,25918,26111); patients should be monitored closely.

Neurologic/CNS ...Orally, high-dose niacin has been associated with cases of neuropsychiatric adverse events such as extreme pain and psychosis. Two 65-year-old males taking niacin orally for 5 months for the treatment of dyslipidemias developed severe dental and gingival pain. The pain was relieved by the discontinuation of niacin. The pain was thought to be due to inflammation and pain referral to the teeth (4862). In one case report, a 52-year-old male with no history of psychiatric illness who initially complained of hot flushes when taking niacin 500 mg daily, presented with an acute psychotic episode involving mania after niacin was increased to 1000 mg daily (93350).

Ocular/Otic ...Orally, chronic use of large amounts of niacin has been associated with dry eyes, toxic amblyopia, blurred vision, eyelid swelling, eyelid discoloration, loss of eyebrows and eyelashes, proptosis, keratitis, macular edema, and cystic maculopathy, which appear to be dose-dependent and reversible (4863,6243,26112).

(Read more about NIACIN)