Two caplets contain: Niacin 25 mg • Uncariae 50 mg • Black Bear Herbal Blend 450 mg: Epimedium grandiflorum , Cyanorium Songaricum , Rehmannia Rhizoma , Radix Cistanches , Cinnamomum Cassiae , Ceruces Nipon , Eucommia , Ulmoides , Fo-Ti Pocoder, Morinda Officinalis , Semen Cuscutace , Semen Psorelea , Polygonum Multiflorum .
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Below is general information about the effectiveness of the known ingredients contained in the product Stim-U Sens 39. Some ingredients may not be listed. This information does NOT represent a recommendation for or a test of this specific product as a whole.
INSUFFICIENT RELIABLE EVIDENCE to RATE
INSUFFICIENT RELIABLE EVIDENCE to RATE
INSUFFICIENT RELIABLE EVIDENCE to RATE
Below is general information about the safety of the known ingredients contained in the product Stim-U Sens 39. Some ingredients may not be listed. This information does NOT represent a recommendation for or a test of this specific product as a whole.
There is insufficient reliable information available about the safety of ba ji tian.
PREGNANCY AND LACTATION:
Insufficient reliable information available; avoid using.
POSSIBLY UNSAFE ...when used orally. Fo-ti has been linked to several cases of liver damage (7626,7627,14327,14347,14482,16459,17192,50711,50727,50729) (92892,92895,112231).
CHILDREN: POSSIBLY UNSAFE
when used orally.
Fo-ti has been linked to several cases of liver damage in adults and at least one case in a 5-year-old child (14339,92895).
PREGNANCY: POSSIBLY UNSAFE
when used orally.
Fo-ti contains anthraquinone constituents, which can exert a stimulant laxative effect. Bulk-forming or emollient laxatives are preferred in pregnancy (272). Fo-ti has also been linked to several cases of liver damage (7626,7627,14327). There is insufficient reliable information available about the safety of fo-ti when used topically during pregnancy.
LACTATION: POSSIBLY UNSAFE
when used orally.
Anthraquinone constituents can cross into breast milk and might cause loose stools in some breast-fed infants (272). Fo-ti has also been linked to several cases of liver damage (7626,7627,14327). There is insufficient reliable information available about the safety of fo-ti when used topically during lactation.
POSSIBLY SAFE ...when horny goat weed extract is used orally and appropriately, short-term. A specific extract of horny goat weed containing 60 mg icariin, 15 mg daidzein, and 3 mg genistein (Xianling Gubao; Tong Ji Tang Pharmacal Company) has been used daily with apparent safety for up to 24 months (14900,97268). Another aqueous extract of horny goat weed containing up to 25.36% icariin has been used in a dose of 300 mL daily with apparent safety for up to 6 months (55452). Another horny goat weed extract has been used with apparent safety at doses up to 1000 mg daily (providing 200 mg icariin) for up to 30 days (108311).
POSSIBLY UNSAFE ...when used orally long-term or in high doses. Long-term use, or taking high doses of some species of horny goat weed, has been linked to serious adverse effects including respiratory arrest (10346).
PREGNANCY: POSSIBLY UNSAFE
when used orally.
Horny goat weed might have androgenic activity (10346). Theoretically, it might harm a developing fetus; avoid using.
LACTATION:
Insufficient reliable information available; avoid using.
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.
Below is general information about the interactions of the known ingredients contained in the product Stim-U Sens 39. Some ingredients may not be listed. This information does NOT represent a recommendation for or a test of this specific product as a whole.
Animal research shows that taking ba ji tian extracts might increase or decrease blood glucose levels (33264). Theoretically ba ji tian might have additive effects or attenuate the effects antidiabetes drugs. Monitor blood glucose levels closely; dose adjustments of antidiabetes drugs might be necessary. Some antidiabetes drugs include glimepiride (Amaryl), glyburide (DiaBeta, Glynase PresTab, Micronase), insulin, metformin (Glucophage), pioglitazone (Actos), rosiglitazone (Avandia), and others.
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Theoretically, fo-ti might increase the risk of hypoglycemia when taken with antidiabetes drugs.
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Theoretically, taking large amounts of fo-ti might interfere with contraceptive drugs due to competition for estrogen receptors.
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Theoretically, fo-ti might increase or decrease the levels and clinical effects of drugs metabolized by CYP1A2.
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In vitro research suggests that fo-ti might inhibit CYP1A2 (12479,112351). Additionally, in vitro research suggests that the degree of CYP1A2 inhibition depends on the type of fo-ti extract (i.e., the raw plant leads to greater inhibition than extensively processed extracts) (112351). However, in an animal study, an aqueous extract of fo-ti inhibited CYP1A2 while an alcoholic extract of fo-ti induced CYP1A2 (92898). Induction or inhibition of CYP1A2 by fo-ti has not been reported in humans.
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Theoretically, fo-ti might increase the levels and clinical effects of drugs metabolized by CYP2B6.
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Animal research suggests that fo-ti might inhibit CYP2B6 (92898). One in vitro study suggests that the degree of CYP2B6 inhibition may depend on the type of fo-ti extract (i.e., the raw plant leads to greater inhibition than extensively processed extracts) (112351). However, this interaction has not been reported in humans.
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Theoretically, fo-ti may increase the levels and clinical effects of drugs metabolized by CYP2C19.
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Animal and in vitro research suggests that fo-ti may inhibit CYP2C19 (12479,92898,112351). An in vitro study suggests that the degree of CYP2C19 inhibition may depend on the type of fo-ti extract (i.e., the raw plant leads to greater inhibition than extensively processed extracts) (112351). However, this interaction has not been reported in humans.
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Theoretically, fo-ti might increase the levels and clinical effects of drugs metabolized by CYP2C8.
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In vitro research suggests that fo-ti might inhibit CYP2C8 (112351). However, this interaction has not been reported in humans.
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Theoretically, fo-ti may increase the levels and clinical effects of drugs metabolized by CYP2C9.
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Theoretically, fo-ti may increase the levels and clinical effects of drugs metabolized by CYP2D6.
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Animal research suggests that fo-ti might inhibit CYP2D6 (92898). Additionally, an in vitro study suggests that the degree of CYP2D6 inhibition may depend on the type of fo-ti extract (i.e., the raw plant leads to greater inhibition than extensively processed extracts) (112351). However, this interaction has not been reported in humans.
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Theoretically, fo-ti might increase the levels and clinical effects of drugs metabolized by CYP3A4.
Details
In vitro research suggests that fo-ti might inhibit CYP3A4 (12479,112351). One in vitro study suggests that the degree of CYP3A4 inhibition may depend on the type of fo-ti extract (i.e., the raw plant leads to greater inhibition than extensively processed extracts) (112351). However, this evidence conflicts with animal research suggesting that fo-ti does not inhibit CYP3A4 (92898). This interaction has not been reported in humans.
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Theoretically, fo-ti, particularly raw fo-ti root, might increase the risk of hypokalemia and cardiotoxicity when taken with digoxin.
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Theoretically, fo-ti, particularly raw fo-ti root, might increase the risk of hypokalemia when taken with diuretic drugs.
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Theoretically, taking large amounts of fo-ti might interfere with hormone replacement therapy through competition for estrogen receptors.
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Theoretically, fo-ti might increase the risk of liver damage when taken with hepatotoxic drugs.
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Theoretically, fo-ti, particularly raw fo-ti root, might increase the risk of fluid and electrolyte depletion when taken with stimulant laxatives.
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Theoretically, fo-ti might increase or decrease the levels and clinical effects of sulindac.
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Animal research suggests that the type of fo-ti extract might affect the levels of sulindac differently; the raw plant may increase levels, but processed parts may decrease levels (112351). Induction or inhibition of CYP1A2 by fo-ti has not been reported in humans.
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Theoretically, fo-ti might increase the effects and adverse effects of warfarin.
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Fo-ti may have stimulant laxative effects and cause diarrhea, especially when the raw or unprocessed fo-ti root is used (5,12,16459,50733,99855). Diarrhea can increase the effects of warfarin, increase international normalized ratio (INR), and increase the risk of bleeding. Also, fo-ti has been linked to cases of acute liver failure which can decrease clotting factor production and increase the effects of warfarin. In one case, a patient who had been stable on warfarin presented with acute hepatitis and an INR elevated to 14.98. The patient had been taking fo-ti for 90 days prior to admission. Discontinuation of warfarin and fo-ti lead to a decrease in the INR and full recovery (17192).
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Theoretically, horny goat weed might increase the risk of bleeding.
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In vitro research and animal research shows that horny goat weed can inhibit platelet aggregation and thrombus formation (105832). This effect has not been reported in humans.
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Theoretically, horny goat weed might increase the risk of hypotension.
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Laboratory research suggests that horny goat weed might have hypotensive effects (10346). This effect has not been reported in humans.
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Theoretically, horny goat weed might increase the effects and side effects of CYP1A2 substrates.
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In vitro, horny goat weed leaf extract inhibits CYP1A2 (97267). This effect has not been reported in humans.
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Theoretically, horny goat weed might increase the effects and side effects of CYP2B6 substrates.
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In vitro, horny goat weed leaf extract inhibits CYP2B6 (97267). This effect has not been reported in humans.
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Theoretically, horny goat weed might increase the effects and side effects of CYP3A4 substrates.
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In vitro, horny goat weed extract inhibits CYP3A4 and suppresses CYP3A4 mRNA expression (112708). This effect has not been reported in humans.
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Theoretically, concomitant use of horny goat weed with estrogens might increase their therapeutic and adverse effects.
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Concomitant use of alcohol and niacin might increase the risk of flushing and hepatotoxicity.
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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.
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Theoretically, niacin might antagonize the therapeutic effects of uricosurics such as allopurinol.
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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).
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Theoretically, niacin may have additive effects when used with anticoagulant or antiplatelet drugs.
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Niacin can increase blood glucose levels and may diminish the effects of antidiabetes drugs.
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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).
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Theoretically, niacin may increase the risk of hypotension when used with antihypertensive drugs.
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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).
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Large doses of aspirin might alter the clearance of niacin.
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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).
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Bile acid sequestrants can bind niacin and decrease absorption. Separate administration by 4-6 hours to avoid an interaction.
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In vitro studies show that colestipol (Colestid) binds about 98% of available niacin and cholestyramine (Questran) binds 10% to 30% (14511).
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Theoretically, concomitant use of niacin and gemfibrozil might increase the risk of myopathy in some patients.
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Theoretically, concomitant use of niacin and hepatotoxic drugs might increase the risk of hepatotoxicity.
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Theoretically, concomitant use of niacin and statins might increase the risk of myopathy and rhabdomyolysis in some patients.
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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).
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Theoretically, niacin might antagonize the therapeutic effects of uricosurics such as probenecid.
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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).
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Theoretically, niacin might antagonize the therapeutic effects of uricosurics such as sulfinpyrazone.
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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).
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Theoretically, niacin might antagonize the therapeutic effects of thyroid hormones.
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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.
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Theoretically, concomitant use of niacin and transdermal nicotine might increase the risk of flushing and dizziness.
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Below is general information about the adverse effects of the known ingredients contained in the product Stim-U Sens 39. Some ingredients may not be listed. This information does NOT represent a recommendation for or a test of this specific product as a whole.
General ...No adverse effects have been reported. However, a thorough evaluation of safety outcomes has not been conducted.
General
...Orally, fo-ti may be unsafe.
Most Common Adverse Effects:
Orally: Abdominal pain, diarrhea, nausea, and vomiting with use of unprocessed fo-ti.
Serious Adverse Effects (Rare):
Orally: Hepatotoxicity with processed or unprocessed fo-ti.
Dermatologic ...Orally, one case of a fine maculopapular rash was reported in a patient taking the herbal product known as Shen-Min, which contains fo-ti. Symptoms resolved within three weeks after discontinuing the product (14482). It is unclear if the rash was due to fo-ti or other ingredients in the herbal product.
Gastrointestinal ...Orally, unprocessed fo-ti may cause diarrhea, abdominal pain, nausea, and vomiting (12,50733).
Hematologic ...Orally, one case of mild eosinophilia was reported in a patient taking the herbal product known as Shen-Min, which contains fo-ti. Symptoms resolved within three weeks after discontinuing the product (14482). It is unclear if this reaction was due to fo-ti or other ingredients in the herbal product. A case of agranulocytosis was reported in a 65-year-old female taking fo-ti 30 grams/day for 17 days. The patient recovered gradually following a 15-day hospitalization, which included treatment with intravenous steroids and granulocyte colony-stimulating factor (112231).
Hepatic
...Orally, cases of liver damage due to both processed and unprocessed fo-ti have been well documented in the medical literature.
(7626,7627,14327,14339,14347,14482,16459,17192,50711,50726)(50727,50729,92892,92895,112231).
In a systematic review, around 450 cases of hepatitis associated with fo-ti were identified. These cases occurred in patients 5-78 years of age. Liver damage occurred at a wide range of doses, formulations, and durations of intake. The type of liver injury ranged from hepatocellular, to cholestatic, or mixed. Outcomes ranged from full recovery to cirrhosis, liver transplantation, and/or death. The evidence suggests that when the daily fo-ti dose is less than 12 grams, the median time to occurrence of liver damage is 60 days. When the daily fo-ti dose is more than 12 grams, the median time to liver damage is 30 days (92895). Presenting signs and symptoms may include jaundice, abdominal pain, nausea, fatigue, loss of appetite, dark urine, myalgias, and elevations in liver function tests (LFTs), ferritin, transferrin, prothrombin time, and INR (17192,92892). Other manifestations may include fever, skin rash, thrombocytopenia, pancytopenia, and arthralgias. Symptoms and increased LFTs usually seem to resolve within a month after discontinuing fo-ti (7626,7627,14339,14347,14482,16459). In one case series, liver enzymes began to normalize 48 hours after discontinuation of fo-ti and treatment with S-adenosylmethionine, compound glycyrrhizin injection, polyene phosphatidylcholine, and reduced glutathione. All patients were eventually discharged home in stable condition (92892). Rechallenge with fo-ti should not be attempted. A patient who had recovered from hepatitis associated with fo-ti use presented with myalgias and markedly elevated LFTs after a single dose of the herb (17192).
It is thought that this idiosyncratic reaction leading to liver damage is at least partially related to genetic polymorphisms. Cytochrome P450 1A2 (CYP1A2) is the predominant enzyme involved in biotransformation of emodin, a constituent of fo-ti thought to play a role in liver damage. In one genetic study, the frequency of CYP1A2*1C mutation in fo-ti induced drug-induced liver injury patients was 46.5%, which is significantly higher than the 27.9% frequency of liver injury reported in healthy patients without the mutation. Patients with a CYP1A2*1C mutation may have decreased activity of the CYP1A2 enzyme, which could inhibit the metabolism of fo-ti, causing an accumulation of toxic substances (92897).
General
...Orally, horny goat weed seems to be well tolerated when used short-term.
Most Common Adverse Effects:
Orally: Dizziness, dry mouth, nosebleed, thirst, and vomiting.
Serious Adverse Effects (Rare):
Orally: Respiratory arrest.
Cardiovascular ...A 66-year-old male with a history of cardiovascular disease developed tachyarrhythmia after taking horny goat weed for 2 weeks (13006). It is not clear if this product contained only horny goat weed or a combination of ingredients; therefore, assigning causality is not possible.
Gastrointestinal ...Orally, long-term use of horny goat weed has been associated with reports of vomiting, dry mouth, thirst, and nosebleed (10346).
Hepatic ...A case of hepatotoxicity characterized by abdominal pain, nausea, vomiting, and fever has been reported in a 40-year-old male patient with hepatitis C, after a month of taking one tablet daily of a combination product containing horny goat weed and multiple other ingredients (Enzyte, Vianda). Symptoms improved following cessation of the product, but it is not clear if they were due to horny goat weed, another ingredients, or hepatitis C (91590). An observational study over 24 years found 26 cases of drug-induced hepatoxicity associated with horny goat weed (112707).
Musculoskeletal ...Orally, large doses of horny goat weed may cause exaggeration of tendon reflexes to the point of spasm (10346).
Neurologic/CNS ...Orally, long-term use of horny goat weed has been associated with reports of dizziness (10346).
Psychiatric ...There is a case report of hypomania in a 66-year-old male who took horny goat weed for 2 weeks (13006). It is not clear if this product contained only horny goat weed or a combination of ingredients; therefore, assigning causality is not possible.
Pulmonary/Respiratory ...Orally, large doses of horny goat weed may cause respiratory arrest (10346).
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).