Two capsules contain: Niacin (inositol hexanicotinate) 200 mg • CoQ10 60 mg • Policosanol (from sugar cane wax) 20 mg • Grape seed extract (90% OPCs) 50 mg.
Brand name products often contain multiple ingredients. To read detailed information about each ingredient, click on the link for the individual ingredient shown above.
Below is general information about the effectiveness of the known ingredients contained in the product Cholesterol Support. 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
INSUFFICIENT RELIABLE EVIDENCE to RATE
Below is general information about the safety of the known ingredients contained in the product Cholesterol Support. Some ingredients may not be listed. This information does NOT represent a recommendation for or a test of this specific product as a whole.
LIKELY SAFE ...when used orally and appropriately. Coenzyme Q10 has been used safely in studies lasting up to 5 years (2134,6037,6038,6407,8163,8938,8939,8940,15395,17413,17716,96538)(109391). ...when used topically on the gums (2107,2108,8916,8917,8918).
CHILDREN: POSSIBLY SAFE
when used orally and appropriately.
Coenzyme Q10 in doses of 1-10 mg/kg/day has been used safely for up to 9 months under medical supervision (12199,13223,15256,44005,107449).
PREGNANCY: POSSIBLY SAFE
when used orally and appropriately.
Coenzyme Q10 100 mg twice daily has been used with apparent safety during pregnancy, starting at 20 weeks gestation until term (17201).
LACTATION:
Insufficient reliable information available; avoid using.
LIKELY SAFE ...when used orally in amounts commonly found in foods. Grapes and grape skin extracts have Generally Recognized As Safe (GRAS) status for use in foods in the US (4912).
POSSIBLY SAFE ...when the whole fruit of the grape, or extracts of the fruit, seed, or leaf, are used orally and appropriately in medicinal amounts. Grape seed extracts have been used with apparent safety in doses up to 200 mg daily for up to 11 months (9182,53016) and in doses up to 2000 mg daily for up to 3 months (53149,53190). Specific grape fruit extracts (Stilvid, Actafarma; Cognigrape, Bionap srl) have been used with apparent safety in doses up to 250-350 mg daily for 3-12 months or 700 mg daily for 6 months (53254,53256,96198). A specific grape leaf extract (AS 195, Antistax, Boehringer Ingelheim) has been used with apparent safety in doses up to 720 mg daily for up to 3 months (2538,52985,53005,53206). A preparation of dehydrated whole grapes, equivalent to 250 grams of fresh grapes daily, has also been used with apparent safety for up to 30 days (18228). A specific grape seed extract (Enovita; Indena SpA) 150 mg twice daily, standardized to provide at least 95% oligomeric proanthocyanins, has been used with apparent safety for up to 16 weeks (108091) ...when used topically and appropriately. Creams and ointments containing grape seed extract 2% or 5% have been used topically with apparent safety for up to 3 weeks (91539,100955). There is insufficient reliable information available about the safety of other grape plant parts when used topically.
CHILDREN: LIKELY SAFE
when used orally in amounts commonly found in foods.
Grapes and grape skin extracts have Generally Recognized As Safe (GRAS) status for use in foods in the US (4912). However, whole grapes should be eaten with caution in children aged 5 years and under. Whole grapes can be a choking hazard for young children (96193). To reduce the risk of choking, whole grapes should be cut in half or quartered before being given to children. There is insufficient reliable information available about the safety of grape when used in medicinal amounts in children.
PREGNANCY AND LACTATION: LIKELY SAFE
when used orally in amounts commonly found in foods.
There is insufficient reliable information available about the safety of medicinal amounts during pregnancy and breast-feeding; avoid using in amounts greater than what is commonly found in foods.
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.
LIKELY SAFE ...when used orally and appropriately in medicinal amounts. Policosanol seems to be safe when used in doses of 5-80 mg daily for up to 3 years (2927,2928,2929,2930,2931,2943,2944,12166,14298,14336)(14404,14411,65383,89438,89454,89451,100178,103832).
PREGNANCY AND LACTATION:
Insufficient reliable information available; avoid using.
Below is general information about the interactions of the known ingredients contained in the product Cholesterol Support. Some ingredients may not be listed. This information does NOT represent a recommendation for or a test of this specific product as a whole.
Coenzyme Q10 has antioxidant effects. Theoretically, this may reduce the activity of chemotherapy drugs that generate free radicals.
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Theoretically, coenzyme Q10 might have additive effects with antihypertensive drugs.
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Coenzyme Q10 is chemically similar to menaquinone and might have vitamin K-like procoagulant effects, which could decrease the effects of warfarin.
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Concomitant use of coenzyme Q10 and warfarin might reduce the anticoagulant effects of warfarin (2128,6048,6199). Four cases of decreased warfarin efficacy thought to be due to coenzyme Q10 have been reported (2128,6048,11048). However, there is some preliminary clinical research that suggests coenzyme Q10 might not significantly decrease the effects of warfarin in patients who have a stable INR (11905).
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Theoretically, grape extracts may have antiplatelet effects and may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
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Ingesting grape juice with cyclosporine can reduce cyclosporine absorption.
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A small pharmacokinetic study in healthy young adults shows that intake of purple grape juice 200 mL along with cyclosporine can decrease the absorption of cyclosporine by up to 30% when compared with water (53177). Separate doses of grape juice and cyclosporine by at least 2 hours to avoid this interaction.
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Theoretically, grape juice might reduce the levels of CYP1A2 substrates.
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A small pharmacokinetic study in healthy adults shows that ingestion of 200 mL of grape juice decreases phenacetin plasma levels. This is thought to be due to induction of CYP1A2 (2539).
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It is unclear if grape juice or grape seed extract inhibits CYP2C9; research is conflicting.
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In vitro evidence shows that grape seed extract or grape juice might inhibit CYP2C9 enzymes (11094,53011,53089). However, a small pharmacokinetic study in healthy adults shows that drinking 8 ounces of grape juice once does not affect the clearance of flurbiprofen, a probe-drug for CYP2C9 metabolism (11094). The effects of continued grape juice consumption are unclear.
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Theoretically, grape seed extract may increase the levels of CYP2D6 substrates.
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In vitro evidence suggests that grape seed extract might inhibit CYP2D6 enzymes (53011). However, this interaction has not been reported in humans.
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Theoretically, grape seed extract might increase the levels of CYP2E1 substrates.
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In vitro and animal research suggests that grape seed proanthocyanidin extract inhibits CYP2E1 enzymes (52949). However, this interaction has not been reported in humans.
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It is unclear if grape seed extract inhibits or induces CYP3A4; research is conflicting.
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Theoretically, long-term intake of grape seed extract might decrease the effects of midazolam.
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Animal research shows that subchronic ingestions of grape seed extract can increase the elimination of intravenous midazolam by increasing hepatic CYP3A4 activity. Single doses of grape seed extract do not appear to affect midazolam elimination (53011).
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Grape juice might decrease phenacetin absorption.
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A small pharmacokinetic study in healthy adults shows that ingestion of 200 mL of grape juice decreases phenacetin plasma levels. This is thought to be due to induction of cytochrome P450 1A2 (CYP1A2) (2539).
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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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Theoretically, taking policosanol with other antiplatelet or anticoagulant drugs might increase the risk of bruising and bleeding.
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Some clinical research shows that taking policosanol 10-50 mg daily for 7-15 days can inhibit platelet aggregation in healthy patients (2936,2937,2938,103832). Although, one clinical trial shows that taking policosanol 10 mg twice daily for 2 weeks prior to warfarin dosing does not affect warfarin pharmacokinetics or warfarin response (20083). Furthermore, a study in patients undergoing percutaneous coronary intervention with a drug-eluting stent found that taking policosanol 40 mg plus clopidogrel and aspirin daily for 30 days modestly reduced the risk for minor bleeding events when compared with taking clopidogrel and aspirin alone (100684). Until more is known, use with caution.
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Theoretically, policosanol might have additive effects with antidiabetes drugs and increase the risk of hypoglycemia.
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Clinical research shows that policosanol can lower blood glucose levels (100178).
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Concomitant use of policosanol with beta-blockers can cause additive blood pressure-lowering effects.
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Theoretically, concomitant use of policosanol with nitroprusside might cause additive blood pressure-lowering effects.
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Animal research shows that taking policosanol along with nitroprusside can increase the blood pressure-lowering effects of nitroprusside (65374).
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Theoretically, taking policosanol with warfarin might increase the risk of bruising and bleeding.
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Some clinical research shows that taking policosanol 10-50 mg daily for 7-15 days can inhibit platelet aggregation in healthy patients (2936,2937,2938). However, one clinical trial shows that taking policosanol 10 mg twice daily for 2 weeks prior to warfarin dosing does not affect warfarin pharmacokinetics or warfarin response (20083).
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Below is general information about the adverse effects of the known ingredients contained in the product Cholesterol Support. 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
...Orally, coenzyme Q10 is generally well tolerated.
In clinical studies, no serious adverse effects have been reported.
Most Common Adverse Effects:
Orally: Gastrointestinal side effects such as appetite suppression, diarrhea, epigastric discomfort, heartburn, nausea, and vomiting. These generally occur in less than 1% of patients. Some of these adverse effects can be minimized if daily doses above 100 mg are divided.
Cardiovascular ...Palpitations have been reported as being possibly associated with coenzyme Q10 treatment (89421). Death due to myocardial infarction occurred in one Parkinson disease patient taking coenzyme Q10; causality is unclear (15395).
Dermatologic ...Two of 143 participants in a case series reported skin itching after starting treatment with oral coenzyme Q10 (6047). Allergic rash has also been reported (6409,11872). An itching exanthema was seen in two heart failure patients treated with intravenous coenzyme Q10 (44284).
Gastrointestinal ...Gastrointestinal side effects of coenzyme Q10 have included nausea (3365,6409,8907,10152,43982,44172,44179,44330,89421,109392), vomiting (3365,10152,44330,89421), epigastric discomfort (3365,44179,44330,89421), constipation (109392), diarrhea (44179,92904,89421,109392), stomach upset (8940,12170,109387,109388,109392), loss of appetite (2121), heartburn (2121,44179,109392), and flatulence (43982), although this occurs in less than 1% of patients. In one clinical study, gastrointestinal bleeding in association with angiodysplasia has been reported to be possibly related to coenzyme Q10 treatment (89421).
Genitourinary ...An uncomplicated urinary infection was reported in a patient taking oral coenzyme Q10 (nanoQuinon, MSE Pharmazeutika) (44020).
Hematologic ...Thrombocytopenia was noted in one patient treated with oral coenzyme Q10 (44296); however, other factors (viral infection, other medications) may have been responsible for this adverse effect.
Musculoskeletal ...Increased plasma creatine kinase with high-intensity exercise has been reported in patients taking coenzyme Q10 (44303). Muscle pain has been reported rarely in one clinical trial (109392).
Neurologic/CNS ...Headache and dizziness have been reported in human research (3365,11872,43982,44330,109392). Insomnia has been reported as being possibly associated with coenzyme Q10 treatment (89421). Cognitive decline, depression, and sudden falls were reported rarely in a clinical trial of patients with Huntington disease (8940). Increased lethargy was reported for one patient treated with oral coenzyme Q10 (44042). Feeling of internal trembling has been reported in a clinical trial for one patient treated with coenzyme Q10 (44020).
Ocular/Otic
...Visual sensitivity to light has been reported for a patient treated with coenzyme Q10.
However, the association of this effect with coenzyme Q10 treatment was not clear (6409).
A burning sensation has been reported for 10% of patients treated with a topical eye solution containing coenzyme Q10 and alpha-tocopheryl polyethylene glycol 1000 succinate following cataract surgery (44228).
Psychiatric ...Worsening depression has been reported as being possibly associated with oral coenzyme Q10 treatment (89421).
Pulmonary/Respiratory ...Drug-induced pneumonitis was diagnosed in a 61 year-old woman who had been taking coenzyme Q10 and perilla leaf extract for two months (43978). Symptoms improved after she stopped taking the supplements and began taking oral prednisone. Causation from coenzyme Q10 was unclear.
Other ...In a case report, a naval aviator using a supplement containing coenzyme Q10 and niacin had reduced G tolerance (44186). G tolerance was regained with cessation of the supplement.
General
...Orally, the whole fruit, as well as the seed, fruit, and leaf extracts, seem to be well tolerated.
Topically, grape seed extracts seem to be well tolerated.
Most Common Adverse Effects:
Orally: Abdominal pain, diarrhea, dry mouth, dyspepsia, headache, joint pain, and nausea.
Serious Adverse Effects (Rare):
Orally: Anaphylaxis to grape skin has been reported.
Dermatologic ...Orally, mild hair thinning has been reported in a patient taking a specific grape leaf extract AS195 KG) (2538). Urticaria (hives) has also been reported with this same extract (53206). Cases of contact dermatitis have been reported in grape workers, including those working in California vineyards (53270,53272,53275).
Gastrointestinal ...Orally, abdominal pain and nausea have been reported with use of grape seed extract, but these effects typically occur at rates similar to placebo (9182,13162). In a case report of a 57-year-old man, intermittent nausea, vomiting, and diarrhea occurred over a 10-day period and improved once grape seed extract was stopped (96764). Gastrointestinal adverse effects have also been reported with use of a different grape seed extract (Entelon, Hanlim Pharm). However, the specific types of gastrointestinal effects were not described (100954). A specific grape leaf extract AS195 (Antistax, Boehringer Ingelheim Pharma GmbH & Co. KG) has reportedly caused flatulence, mild constipation, gastrointestinal discomfort, diarrhea, dyspepsia, dry mouth, and retching (2538,52985,53206). Diarrhea, gastrointestinal distress, indigestion, and aversion to taste have been reported with use of Concord grape juice (52972,53166,53175,53181,53199). Loose stools have been reported in a clinical trial of grape pomace (99270). Bowel obstruction caused by intact grapes and grape seeds has been described in case reports (53241,53284,53278). Excessive consumption of grapes, dried grapes, raisins, or sultanas might cause diarrhea due to laxative effects (4201).
Hematologic ...Orally, one case of leg hematoma following a minor trauma was reported in a person using grape leaf extract (2538). Also, one case of bruising was reported in a person drinking Concord grape juice daily for 2 weeks (52972).
Immunologic ...Orally, there is one report of an anaphylactic reaction to oral grape skin extract, which included urticaria and angioedema (4073).
Musculoskeletal ...Orally, musculoskeletal disorders, including back pain, have been reported with use of a specific grape leaf extract AS195 KG) (2538,53206). Joint pain and lumbago have been reported with use of grape seed extract, but these effects occur at rates similar to placebo (91541).
Neurologic/CNS ...Orally, headache has been reported with use of grape seed extract, but this effect occurs at rates similar to placebo (9182,91541). A specific grape leaf extract AS195 (Antistax, Boehringer Ingelheim Pharma GmbH & Co. KG) has reportedly caused dizziness, tiredness, headache, and sleep problems (2538,53206). As a class, nervous system adverse effects have been reported with use of a specific grape seed extract (Entelon, Hanlim Pharm). However, the specific types of adverse neurologic effects were not described (100954).
Ocular/Otic ...Orally, ocular adverse effects have been reported with use of a specific grape seed extract (Entelon, Hanlim Pharm). However, the specific types of ocular adverse effects were not described (100954).
Pulmonary/Respiratory ...Orally, nasopharyngitis and oropharyngeal pain have been reported with use of a specific grape leaf extract AS195 KG) (53206). Sore throat, cough, allergic rhinitis, and nasopharyngitis have been reported with use of grape seed extract, but these effects occur at rates similar to placebo (9182,91541). One case report describes a 16-year-old female who developed increased levels of immunoglobulin E (IgE) following skin-prick exposure to grape vine pollen, as well as positive test responses following bronchial and conjunctival provocation (53301). Reduced forced vital capacity has been described in California grape workers (53080,53081). Occupational eosinophilic lung was diagnosed in a grape grower with a history of asthma. Respiratory exposure to sulfites in grape was implicated as the cause of the adverse reaction (53285).
Other
...Orally, grape products can cause adverse effects due to contamination with pesticides or mycotoxins.
Some evidence has shown that pesticides used in vineyards may remain on grape surfaces post-harvesting. For example, the fungicide folpet sprayed on grapevines has been shown to remain on the grape surface. Although there was minimal penetration of the epicuticular wax, it showed high resistance to washing (52935). Carbaryl has been identified in over 58% of juice samples collected in Canada. This pesticide reportedly occurred more frequently in grape than in other juices. However, estimates of short-term intake were below proposed acute reference doses (53003).
Ochratoxin A is a mycotoxin that is suspected to be nephrotoxic, teratogenic, hepatotoxic and carcinogenic and has been identified in grape juice, frozen grape pulps, and red and white wine sold in Rio de Janeiro, Brazil. However, the highest levels identified in grape products were lower than the established virtually safe dose of 5 ng/kg of body weight daily (53010,53004). Ochratoxin A has also been identified in red, but not white, grape juice marketed in Switzerland, Canada, and the U.S. (53292,53020).
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).
General
...Orally, policosanol is usually well-tolerated.
Most Common Adverse Effects:
Orally: Dysuria, headache, insomnia, polyphagia, pruritis, skin rash, somnolence, upset stomach, vertigo, weight loss.
Dermatologic ...Orally, policosanol can cause pruritus or skin rash, but these events appear to be uncommon (65369,95374,100178). In one clinical trial that included over 50 patients, one case of policosanol-associated skin rash was reported (65369). In another study, 1 out of 40 patients treated with policosanol 10 mg daily reported pruritus (95374).
Gastrointestinal ...Orally, policosanol can cause upset stomach or polyphagia (2937).
Genitourinary ...Orally, policosanol can cause dysuria (2937).
Hematologic ...A case gum bleeding has been reported in a patient taking policosanol 20 mg and aspirin 100 mg daily for 7 days (2937).
Neurologic/CNS ...Orally, policosanol may cause headache, mild vertigo, somnolence, irritability, or insomnia but these events are uncommon. In one clinical study, 1 out of 44 subjects receiving policosanol 20 mg daily 12 weeks experienced mild vertigo and 2 out of 44 experienced mild headache (14404). In another study, 2 out of 70 patients taking policosanol 10 mg daily for 8 weeks experienced headache (69119). In another study, 1 out of 40 patients taking policosanol 10 mg daily reported insomnia (95374).
Other ...Orally, policosanol has been associated with weight loss. However, evidence from a post-market surveillance study of patients taking policosanol 5-15 mg daily shows that this adverse event is uncommon (95375).