Interactions on record — worth a quick check against your medications. Check your meds →
Dietary supplement

Double Strength Flush-Free Niacin 500 mg Ingredients & Drug Interactions

by NOW

Double Strength Flush-Free Niacin 500 mg label
See full label image
Capsule Category: Other Combinations
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Double Strength Flush-Free Niacin 500 mg against your medications. The heart of this page is the interaction checker and the full interaction report — how this product’s ingredients may interact with prescription and over-the-counter medicines you may be taking.

Around that, we add a pharmacist’s high-level view of the product as a whole — what’s inside, the evidence for its stated use, how transparent the label is, and what safety data exists — so you can see the full picture in one place. It’s educational information from our licensed clinical databases and the clinical staff at HelloPharmacist — not medical advice — and we don’t sell or endorse products. Our editorial policy

The interaction bottom line Most serious interaction: Moderate

Double Strength Flush-Free Niacin 500 mg is a dietary supplement by NOW with 1 active ingredient. Its ingredients are commonly taken for cholesterol support, improving circulation, raynaud's phenomenon.Based on those ingredients, 727 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Inositol Hexanicotinate. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Double Strength Flush-Free Niacin 500 mg by NOW

Ask about any prescription or over-the-counter medication and we check it for interactions with Double Strength Flush-Free Niacin 500 mg by NOW — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Double Strength Flush-Free Niacin 500 mg by NOW

Our pharmacy team’s full take, with four database checks built into the cards below — a summary of what is known, not a grade of the product itself.

From our pharmacy team — supplement deep dive

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Jul 23, 2026

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 2 of its 2 active ingredients.
  • “Inositol Hexanicotinate” is listed as a grouped ingredient — the label gives one combined amount (640 mg) without saying how much of each component you get.

This product contains 2 active ingredients: niacin 500 mg (the "flush-free" form is niacin hexanicotinate, designed to reduce the skin-flushing side effect common with standard niacin) and inositol. Niacin is a B vitamin that helps your body convert food into energy and supports cholesterol and blood sugar metabolism.

Inositol is a naturally occurring compound that plays a role in cell signaling and insulin action. The capsule also contains inactive ingredients: hypromellose, stearic acid, rice flour, and silicon dioxide.

Does it work?

Strong evidence
Evidence for Intended Use · database check
By FDA rules, dietary supplements can’t claim to treat, cure, or prevent disease — so labels speak in careful marketing language. We discern each product’s intended use from its name, label claims, and label statements, then grade the clinical evidence for that use. How these ratings are computed
Strong

Clinical evidence supports at least one of this product's ingredients for its stated purpose.

Why this rating?
  • The label markets this product for: Niacin B-vitamin and circulation support.
  • We looked for evidence on: Dyslipidemia, Hyperlipidemia, Intermittent claudication, Raynaud syndrome, Pellagra, Heart health — and 1 related terms.
  • The strongest evidence on file: Niacin is rated "Likely Effective" for Pellagra (Natural Medicines).
  • Also on file: Niacin is rated "Possibly Effective" for HIV/AIDS-related dyslipidemia.
  • Also on file: Inositol is rated "Insufficient Reliable Evidence To Rate" for Dyslipidemia.

Niacin is likely effective for pellagra (a serious niacin deficiency disease) and possibly effective for HIV/AIDS-related high cholesterol and metabolic syndrome. Inositol is possibly effective for polycystic ovary syndrome (PCOS), metabolic syndrome, and preterm labor risk, but the evidence suggests it's likely ineffective for anxiety, diabetic nerve pain, and depression.

The evidence, ingredient by ingredient Inositol Nicotinate Niacin Inositol

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

Adverse-effect, pregnancy, and general safety data are on file for most of these ingredients.

Why this rating?
  • We hold adverse-effect (side-effect) data for 2 of the 2 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 2 of 2.
  • General safety write-ups exist for 2 of 2.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Niacin from food is safe, but high-dose supplements can cause flushing (redness and tingling of the skin, reported in up to 70% of people), gastrointestinal upset, and liver problems. The adverse effects listed include gastrointestinal complaints (nausea, vomiting, heartburn, abdominal pain, diarrhea, constipation) and elevated liver enzymes as most common; serious but rare effects include liver damage, muscle damage, low blood platelets (clotting cells), and vision changes.

Inositol is generally well tolerated with mostly mild digestive side effects like diarrhea, gas, and nausea. For pregnancy, niacin at normal dietary and prenatal vitamin amounts is likely safe, but high-dose supplements should be avoided unless prescribed by your doctor.

Inositol is possibly safe in pregnancy but only under medical supervision since full safety data aren't established. For breastfeeding, normal dietary niacin is fine; insufficient data exists for inositol during lactation.

Side effects, ingredient by ingredient Inositol Nicotinate Niacin Inositol

Meds to double-check

Moderate interaction found
Known Interaction Concern · database check
Moderate identified

The most serious documented interaction for these ingredients is Moderate. Check your medications for a personalized result.

Why this rating?
  • 2 of the 2 matched ingredients can interact with medications — Inositol, Niacin.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; diabetes medications.
  • For scale: 728 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Before taking this product, check with your doctor or pharmacist if you take antihypertensive drugs (blood pressure medications), hepatotoxic drugs (liver-damaging medications), antidiabetes drugs, blood thinners or antiplatelet drugs, statins, allopurinol or probenecid (gout medications), or bile acid sequestrants (cholesterol medications). All carry moderate-severity interactions with niacin or inositol in this product.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with clinical evidence supporting its stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.

This product is used for niacin deficiency and as a supplement for cholesterol and blood sugar support. If you take medications for blood pressure, diabetes, blood clotting, cholesterol (especially statins), gout, or liver function, talk with your doctor or pharmacist before starting—niacin has several moderate interactions.

If you're pregnant or breastfeeding, check with your healthcare provider first. Use the interaction checker below to verify your specific medications.

Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI

Assessment coverage: 2 of 2 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Feb 25, 2021.

This Scorecard evaluates available label information, ingredient evidence, and known medication-safety considerations. It does not independently verify product identity, purity, potency, contamination, or manufacturing quality. How these ratings are computed

At a glance

General information

Key facts about Double Strength Flush-Free Niacin 500 mg, straight from the product label.

Brand NOW
Barcode (UPC) 733739005007
Net contents 180 Veg Capsule(s)
Market status On market
Date entered into DSLD Feb 25, 2021
DSLD ID 244582
Product type Other Combinations
Supplement form Capsule
Dietary claims / uses Nutrient, All Other, Structure/Function
Intended target group(s) Vegan, Vegetarian, Adult (18 - 50 Years), Kosher, Gluten Free
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for Double Strength Flush-Free Niacin 500 mg by NOW, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
1 Veg Capsule(s)
Maximum serving Sizes:
1 Veg Capsule(s)
Servings per container
180
UPC/BARCODE
733739005007
IngredientAmount% DV
Niacin500 mg3125%
Inositol135 mg--
Inositol Hexanicotinate640 mg--

Other ingredients: Hypromellose, Stearic Acid, Rice Flour, Silicon Dioxide

Tap any ingredient to jump to its full detail below.

Label statements
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
Suggested/Recommended/Usage/Directions

Suggested Usage: Take 1 capsule daily as needed, with a meal.

Formulation

Niacin (Vitamin B-3) is an essential B-Complex vitamin.

Non-GMO

Vegetarian/Vegan

Not manufactured with wheat, gluten, soy, milk, egg, fish, shellfish or tree nut ingredients.

Formula

Flush-free niacin contains inositol hexanicotinate, a form of niacin that consists of six molecules of niacin linked to a single inositol molecule. It is slowly broken down in the body to yield free niacin and inositol. This gradual release of niacin allows for true niacin activity without the characteristic niacin flush that many people cannot tolerate.

Triangle K (Kosher)

Inositol hexanicotinate is a stable, non-flushing source of niacin. This superior source of niacin works to reduce the common “niacin-flush” problems associated with high doses of niacin supplements.

This product has twice the Niacin (500 mg per capsule) as in our regular strength product (250 mg per capsule).

Precautions

Caution: For adults only.

Consult physician if pregnant/nursing, taking medication, or have a medical condition (liver problems, stomach ulcers, diabetes, gout, etc.).

Keep out of reach of children.

Not manufactured with wheat, gluten, soy, milk, egg, fish, shellfish or tree nut ingredients. Produced in a GMP facility that processes other ingredients containing these allergens.

General Statements

Natural color variation may occur in this product.

Nutritional Health

Vitamins Family owned since 1968.

Storage

Store in a cool, dry place after opening.

FDA Statement of Identity

A Dietary Supplement

Seals/Symbols

Triangle K (Kosher)

GMP Quality Assured

Is this label outdated? Report a formula or label change and our pharmacy team will review it.

See for yourself

Double Strength Flush-Free Niacin 500 mg by NOW label

The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.

Double Strength Flush-Free Niacin 500 mg label

Label images are published by the NIH Dietary Supplement Label Database for the version of this product on file. Always read your actual product label.

View the full label (PDF)
What’s inside

The Ingredients in Double Strength Flush-Free Niacin 500 mg by NOW

This is the 1 active ingredient this product is made of. Select it to open its full monograph.

Serving size1 Veg Capsule(s) Dosage formCapsule Servings per container180 Amounts shown are per serving.

Inositol Hexanicotinate

Interacts with
223 drugs
640 mg per serving

Inositol nicotinate is a 'no-flush' form of niacin marketed for cholesterol and circulation. Evidence that it works as well as regular niacin is weak...

Inositol Hexanicotinate monograph & interactions

Other (inactive) ingredients: Hypromellose, Stearic Acid, Rice Flour, Silicon Dioxide. These complete the product’s ingredient list but are not active constituents.

Interaction report

Double Strength Flush-Free Niacin 500 mg by NOW Drug Interactions

Want to check YOUR meds against Double Strength Flush-Free Niacin 500 mg?

Ask about interactions with your drugs in plain English — “Can I take it with lisinopril?” — and we find you the answer in seconds, ingredient by ingredient.

 Go to the checker
727Drugs
727 Moderate

Ingredients driving the most interactions

Inositol Hexanicotinate 223

Individual Drug Interactions

The ingredients in Double Strength Flush-Free Niacin 500 mg interact with 727 drugs. Click any drug to see the details.

1 of the 1 ingredient in Double Strength Flush-Free Niacin 500 mg interact with drugs. Each result below shows which ingredient is responsible. Inositol Hexanicotinate

Each ingredient & the kinds of drugs it affects

For each ingredient in Double Strength Flush-Free Niacin 500 mg with known interactions, here are the types of medications it can affect. Open any type for the detail — or search your exact drug in the checker above.

Inositol Hexanicotinate4 drug types · 223 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, concomitant use of inositol nicotinate with anticoagulant or antiplatelet drugs might increase the risk of bleeding.
Inositol nicotinate has fibrinolytic effects, which may increase the risk of bleeding when used concomitantly with anticoagulant/antiplatelet drugs.

Likelihood Possible Evidence D
Antidiabetes Drugs

Theoretically, inositol nicotinate might increase blood glucose levels and may diminish the effects of antidiabetes drugs.
Inositol nicotinate is metabolized to niacin in the body. Niacin can cause hyperglycemia, abnormal glucose tolerance, and glycosuria. Increased blood glucose monitoring may be necessary, particularly early in the course of treatment.

Likelihood Probable Evidence B
Hmg-Coa Reductase Inhibitors ("Statins")

Theoretically, concomitant use of inositol nicotinate and statins might increase the risk of myopathy and rhabdomyolysis.
Inositol nicotinate is metabolized to niacin in the body. Some case reports have raised concerns that niacin might increase the risk of myopathy and rhabdomyolysis when combined with statins However, a significantly increased risk of myopathy has not been demonstrated in clinical trials.

Likelihood Possible Evidence D
Transdermal Nicotine (Nicoderm)

Theoretically, concomitant use of inositol nicotinate and transdermal nicotine might increase the risk of flushing and dizziness.
Inositol nicotinate is metabolized to niacin in the body. Inositol nicotinate and nicotine can both cause flushing and dizziness.

Likelihood Possible Evidence D
Inositol Hexanicotinate full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Double Strength Flush-Free Niacin 500 mg, from the product label.

NOW

See all NOW products
Name
NOW Foods
Street Address
395 S. Glen Ellyn Rd.
City
Bloomingdale
State
IL
ZipCode
60108
Web Address
nowsportsproducts.com
Pharmacist Counseling Corner

Double Strength Flush-Free Niacin 500 mg by NOW: Common Questions

Does Double Strength Flush-Free Niacin 500 mg by NOW interact with any medications?
Yes. Based on its ingredients, Double Strength Flush-Free Niacin 500 mg has a known interaction with 727 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Double Strength Flush-Free Niacin 500 mg contains a single active ingredient, and that one ingredient can interact with many different medications on its own. We check it against each medication and show the mechanism responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
What's the difference between this niacin and the kind that causes flushing?
This product contains niacin hexanicotinate, a form designed to reduce flushing (the burning, redness, and tingling of the skin). However, up to 70% of people still experience some flushing, especially at higher doses. Regular niacin typically causes more flushing because it's absorbed faster.
Can I take this if I'm on a statin for cholesterol?
Niacin and statins together carry a moderate interaction—there's a theoretical concern about muscle damage, though it hasn't been proven at typical doses. Don't start this product without clearing it with your doctor first, since your statin dose might need adjusting.
What if I have diabetes or prediabetes?
Both ingredients in this product can raise blood glucose and interfere with diabetes medications. If you take diabetes drugs, talk with your doctor or pharmacist before starting—your blood sugar and medication doses may need monitoring.
Is it safe to take if I'm pregnant?
Normal dietary niacin amounts are safe in pregnancy, but high-dose supplements like this should only be used if prescribed by your doctor. Inositol is possibly safe but also needs medical supervision during pregnancy. Talk with your healthcare provider about whether this product is right for you.
What are the most common side effects I might notice?
Flushing (burning, redness, tingling of the face and neck) is the most common with niacin—it can happen even with this "flush-free" form. Stomach upset including nausea, heartburn, and diarrhea can occur with either ingredient, especially when first starting.
Does this really help with cholesterol and blood sugar?
Niacin is possibly effective for high cholesterol related to HIV/AIDS and metabolic syndrome. Inositol is possibly effective for PCOS and metabolic syndrome. For other uses, the evidence is weaker or suggests it won't help. Talk with your doctor about whether this fits your specific health goals.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

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Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.

Double Strength Flush-Free Niacin 500 mg label
Go deeper

The Full Monographs Behind Double Strength Flush-Free Niacin 500 mg’s Ingredients

Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.

Herb & supplement monograph

Inositol Nicotinate

Interacts with 223 drugs

Inositol nicotinate is a 'no-flush' form of niacin marketed for cholesterol and circulation. Evidence that it works as well as regular niacin is weak and inconsistent, and it is not a proven...

Read the full Inositol Nicotinate monograph → Herb & supplement monograph

Niacin

Interacts with 727 drugs

Niacin (vitamin B3) is an essential nutrient your body needs for energy and metabolism, and deficiency is uncommon in most developed countries. Prescription-strength niacin has been used to...

Read the full Niacin monograph → Herb & supplement monograph

Inositol

Interacts with 86 drugs

Inositol is a sugar alcohol made naturally in the body and found in many foods, and it is sold as a supplement (often myo-inositol) mainly for PCOS, mood, and metabolic concerns. The stronge...

Read the full Inositol monograph →
Sources

Sources & How We Checked

Double Strength Flush-Free Niacin 500 mg's label data comes from the NIH Dietary Supplement Label Database; the ingredient interaction data is from the Natural Medicines database, reviewed by our pharmacists.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

The 101 references behind this product’s interaction data

Every citation that drives the interaction findings for this product’s ingredients, from the evidence-graded Natural Medicines (TRC Healthcare) database. Open an ingredient to browse its citations — links open the study on PubMed or the publisher’s site.

Niacin 66 references
  1. Garg R, Malinow MR, Pettinger M, et al. Niacin treatment increases plasma homocysteine levels. Am Heart J 1999;138:1082-7.
  2. Anon. Inositol hexaniacinate. Altern Med Rev 1998;3:222-3.
  3. Knodel LC, Talbert RL. Adverse effects of hypolipidaemic drugs. Med Toxicol 1987;2:10-32. PubMed
  4. Guyton JR, Blazing MA, Hagar J, et al. Extended-release niacin vs gemfibrozil for the treatment of low levels of high-density lipoprotein cholesterol. Niaspan-Gemfibrozil Study Group. Arch Intern Med 2000;160:1177-84. PubMed
  5. Gibbons LW, Gonzalez V, Gordon N, Grundy S. The prevalence of side effects with regular and sustained-release nicotinic acid. Am J Med 1995;99:378-85. PubMed
  6. Whelan AM, Price SO, Fowler SF, Hainer BL. The effect of aspirin on niacin-induced cutaneous reactions. J Fam Pract 1992;34:165-8.
  7. Jungnickel PW, Maloley PA, Vander Tuin EL, et al. Effect of two aspirin pretreatment regimens on niacin-induced cutaneous reactions. J Gen Intern Med 1997;12:591-6. PubMed
  8. Capuzzi DM, Guyton JR, Morgan JM, et al. Efficacy and safety of an extended-release niacin (Niaspan): a long-term study. Am J Cardiol 1998;82:74-81;disc. 85U-6U. PubMed
  9. Gray DR, Morgan T, Chretien SD, Kashyap ML. Efficacy and safety of controlled-release niacin in dyslipoproteinemic veterans. Ann Intern Med 1994;121:252-8. PubMed
  10. McKenney JM, Proctor JD, Harris S, Chinchili VM. A comparison of the efficacy and toxic effects of sustained- vs immediate-release niacin in hypercholesterolemic patients. JAMA 1994;271:672-7. DOI
  11. Knopp RH, Alagona P, Davidson M, et al. Equivalent efficacy of a time-release form of niacin (Niaspan) given once-a-night versus plain niacin in the management of hyperlipidemia. Metabolism 1998;47:1097-104. PubMed
  12. Knopp RH. Clinical profiles of plain versus sustained-release niacin (Niaspan) and the physiologic rationale for nighttime dosing. Am J Cardiol 1998;82:24U-28U;discussion 39U-41U. PubMed
  13. Garg A, Grundy SM. Nicotinic acid as therapy for dyslipidemia in non-insulin-dependent diabetes mellitus. JAMA 1990;264:723-6. DOI
  14. Leighton RF, Gordon NF, Small GS, et al. Dental and gingival pain as side effects of niacin therapy. Chest 1998;114:1472-4. PubMed
  15. American Society of Health-System Pharmacists. ASHP Therapeutic Position Statement on the safe use of niacin in the management of dyslipidemias. Am J Health Syst Pharm 1997;54:2815-9. DOI
  16. Vega GL, Grundy SM. Lipoprotein responses to treatment with lovastatin, gemfibrozil, and nicotinic acid in normolipidemic patients with hypoalphalipoproteinemia. Arch Intern Med 1994;154:73-82. DOI
  17. Guyton JR, Goldberg AC, Kreisberg RA, et al. Effectiveness of once-nightly dosing of extended-release niacin alone and in combination for hypercholesterolemia. Am J Cardiol 1998;82:737-43.
  18. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline (2000). Washington, DC: National Academy Press, 2000. Available at: http://b
  19. Brown BG, Zhao XQ, Chait A, et al. Simvastatin and niacin, antioxidant vitamins, or the combination for the prevention of coronary disease. N Engl J Med 2001;345:1583-93. DOI
  20. Bays HE, Dujovne CA. Drug interactions of lipid-altering drugs. Drug Saf 1998;19:355-71. PubMed
  21. Rader JI, Calvert RJ, Hathcock JN. Hepatic toxicity of unmodified and time-release preparations of niacin. Am J Med 1992;92:77-81. PubMed
  22. Kahn SE, Beard JC, Schwartz MW, et al. Increased B-cell secretory capacity as mechanism for islet adaptation to nicotinic acid-induced insulin resistance. Diabetes 1989;38:562-8.
  23. Schwartz ML. Severe reversible hyperglycemia as a consequence of niacin therapy. Arch Int Med 1993;153:2050-2. DOI
  24. Raising HDL and Niacin Use. Pharmacist's Letter/Prescriber's Letter 2004;20(5):200504.
  25. McKenney J. New perspectives on the use of niacin in the treatment of lipid disorders. Arch Intern Med 2004;164:697-705. PubMed
  26. Reaven P, Witztum JL. Lovastatin, nicotinic acid and rhabdomyolysis (letter). Ann Int Med 1988;109:597-8. PubMed
  27. Ito MK. Advances in the understanding and management of dyslipidemia: using niacin-based therapies. Am J Health-Syst Pharm 2003;60(suppl 2):s15-21. PubMed
  28. Schwab RA, Bachhuber BH. Delirium and lactic acidosis caused by ethanol and niacin coingestion. Am J Emerg Med 1991;9:363-5. PubMed
  29. Product information: Niaspan. Kos Pharmaceuticals. Cranbury, NJ. 2005. Available at www.niaspan.com/professional/content/pdfs/productinfo.pdf. (Accessed 3 March 2006).
  30. Ding RW, Kolbe K, Merz B, et al. Pharmacokinetics of nicotinic acid-salicylic acid interaction. Clin Pharmacol Ther 1989;46:642-7. PubMed
  31. NIH News. NIH stops clinical trial on combination cholesterol treatment. May 26, 2011. http://www.nih.gov/news/health/may2011/nhlbi-26.htm. (Accessed 3 June 2011).
  32. Dearing BD, Lavie CJ, Lohmann TP, Genton E. Niacin-induced clotting factor synthesis deficiency with coagulopathy. Arch Intern Med. 1992;152(4):861-3. DOI
  33. O'Brien T, Silverberg JD, Nguyen TT. Nicotinic acid-induced toxicity associated with cytopenia and decreased levels of thyroxine-binding globulin. Mayo Clin Proc. 1992;67(5):465-8. PubMed
  34. Gadegbeku CA, Dhandayuthapani A, Shrayyef MZ, Egan BM. Hemodynamic effects of nicotinic acid infusion in normotensive and hypertensive subjects. Am J Hypertens. 2003;16(1):67-71. PubMed
  35. Garnett WR. Interactions with hydroxymethylglutaryl-coenzyme A reductase inhibitors. Am J Health Syst Pharm. 1995;52(15):1639-45. PubMed
  36. Litin SC, Anderson CF. Nicotinic acid-associated myopathy: a report of three cases. Am J Med. 1989;86(4):481-3. PubMed
  37. Dunn RT, Ford MA, Rindone JP, Kwiecinski FA. Low-Dose Aspirin and Ibuprofen Reduce the Cutaneous Reactions Following Niacin Administration. Am J Ther. 1995;2(7):478-480. PubMed
  38. Cashin-Hemphill L, Spencer CA, Nicoloff JT, et al. Alterations in serum thyroid hormonal indices with colestipol-niacin therapy. Ann Intern Med. 1987;107(3):324-9. PubMed
  39. Drinka PJ. Alterations in thyroid and hepatic function tests associated with preparations of sustained-release niacin. Mayo Clin Proc. 1992;67(12):1206. PubMed
  40. Shakir KM, Kroll S, Aprill BS, Drake AJ 3rd, Eisold JF. Nicotinic acid decreases serum thyroid hormone levels while maintaining a euthyroid state. Mayo Clin Proc. 1995;70(6):556-8. PubMed
  41. Etchason JA, Miller TD, Squires RW, et al. Niacin-induced hepatitis: a potential side effect with low-dose time-release niacin. Mayo Clin Proc. 1991;66(1):23-8. PubMed
  42. Henkin Y, Johnson KC, Segrest JP. Rechallenge with crystalline niacin after drug-induced hepatitis from sustained-release niacin. JAMA. 1990;264(2):241-3. DOI
  43. Henkin Y, Oberman A, Hurst DC, Segrest JP. Niacin revisited: clinical observations on an important but underutilized drug. Am J Med. 1991;91(3):239-46. PubMed
  44. Brown BG, Bardsley J, Poulin D, et al. Moderate dose, three-drug therapy with niacin, lovastatin, and colestipol to reduce low-density lipoprotein cholesterol <100 mg/dl in patients with hyperlipidemia and coronary artery disease. Am J Cardiol. 1997;80(2)
  45. Goldberg A, Alagona P Jr, Capuzzi DM, et al. Multiple-dose efficacy and safety of an extended-release form of niacin in the management of hyperlipidemia. Am J Cardiol. 2000;85(9):1100-5. PubMed
  46. Aronov DM, Keenan JM, Akhmedzhanov NM, et al. Clinical trial of wax-matrix sustained-release niacin in a Russian population with hypercholesterolemia. Arch Fam Med. 1996;5(10):567-75. PubMed
  47. Morgan JM, Capuzzi DM, Guyton JR, et al. Treatment Effect of Niaspan, a Controlled-release Niacin, in Patients With Hypercholesterolemia: A Placebo-controlled Trial. J Cardiovasc Pharmacol Ther. 1996;1(3):195-202. PubMed
  48. Andersson RG, Aberg G, Brattsand R, Ericsson E, Lundholm L. Studies on the mechanism of flush induced by nicotinic acid. Acta Pharmacol Toxicol (Copenh). 1977 Jul;41(1):1-10. PubMed
  49. Brown WV. Niacin for lipid disorders. Indications, effectiveness, and safety. Postgrad Med. 1995 Aug;98(2):185-9, 192-3. PubMed
  50. O'REILLY PO, CALLBECK MJ, HOFFER A. Sustained-release nicotinic acid (nicospan); effect on (1) cholesterol levels and (2) leukocytes. Can Med Assoc J. 1959;80(5):359-62.
  51. Gharavi AG, Diamond JA, Smith DA, Phillips RA. Niacin-induced myopathy. Am J Cardiol. 1994;74(8):841-2. PubMed
  52. Litin SC, Anderson CF. Nicotinic acid-associated myopathy: a report of three cases. Am J Med. 1989;86(4):481-3. PubMed
  53. Fraunfelder FW, Fraunfelder FT, Illingworth DR. Adverse ocular effects associated with niacin therapy. Br J Ophthalmol 1995;79:54-56. PubMed
  54. Ali EH, McJunkin B, Jubelirer S, Hood W. Niacin induced coagulopathy as a manifestation of occult liver injury. W V Med J. 2013 Jan-Feb;109(1):12-4
  55. Aramwit P, Srisawadwong R, Supasyndh O. Effectiveness and safety of extended-release nicotinic acid for reducing serum phosphorus in hemodialysis patients. J Nephrol. 2012 May-Jun;25(3):354-62. PubMed
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See these in context on the Inositol Nicotinate monograph →

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DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

© 2021 Therapeutic Research Center, LLC

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