Drug & supplement interaction

Niacin + Fluvastatin

Fluvastatin brand names: Lescol, Lescol XL.

Moderate Interaction
Medically reviewed by · Updated September 2026
The bottom line Moderate

Fluvastatin falls into 2 drug categories that Niacin can interact with; the most serious is rated moderate. Theoretically, concomitant use of niacin and hepatotoxic drugs might increase the risk of hepatotoxicity.

Read the full interaction report
SeverityModerate
LikelihoodPossible
Interactions2
EvidenceD
What do Severity, Likelihood & Evidence mean?
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Interaction report

Niacin and Fluvastatin

These two interact in 2 distinct ways. Each one is explained separately below.

Why Are There 2 Interactions?

Niacin interacts with whole categories of medication. Fluvastatin falls into 2 of those categories, so it can interact with Niacin in 2 different ways. We’ve listed each one below — your overall risk is driven by the most serious of them (Moderate).

Moderate

HEPATOTOXIC DRUGS

1 of 2

Why this applies to Fluvastatin

Fluvastatin falls under HEPATOTOXIC DRUGS — the group Niacin interacts with.

Theoretically, concomitant use of niacin and hepatotoxic drugs might increase the risk of hepatotoxicity.
Niacin has been associated with cases of liver toxicity, especially when used in pharmacologic doses. Sustained-release niacin preparations appear to be associated with a higher risk of hepatotoxicity than immediate-release niacin.
Severity Moderate Likelihood Possible Evidence D

Interaction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists.

Dr. Brian Staiger, PharmD, BCPS
Dr. Brian Staiger explains PharmD, Clinical Pharmacist

Here's the connection worth knowing about. Both fluvastatin (Lescol) and high-dose niacin can put some stress on your liver. When you take them together, the concern is that the liver strain could add up, raising the chance of liver irritation. Realistically, this might show up as unusual tiredness, belly pain on the upper right side, dark urine, or yellowing of your skin or eyes. Those would be signs to call your doctor.

I want to keep this in perspective. This is a theoretical concern based on how each one behaves, not something proven to happen often. The normal vitamin B3 in food or a basic multivitamin isn't the worry here, it's the high, cholesterol-dose niacin, especially sustained-release forms. If you're using both, ask your pharmacist or doctor about checking your liver enzymes.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. 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
  2. Bays HE, Dujovne CA. Drug interactions of lipid-altering drugs. Drug Saf 1998;19:355-71. PubMed
  3. Rader JI, Calvert RJ, Hathcock JN. Hepatic toxicity of unmodified and time-release preparations of niacin. Am J Med 1992;92:77-81. PubMed
  4. 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
  5. 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
  6. 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
  7. Bassan M. A case for immediate-release niacin. Heart Lung. 2012 Jan-Feb;41(1):95-8. PubMed
  8. Nawaz N, Mistretta T, Karime C, Lewis J, Wolf E. Cholestatic Drug-Induced Liver Injury in a Patient Taking High-Dose Niacin for Hyperlipidemia. J Investig Med High Impact Case Rep 2024;12:23247096231224349. PubMed
Moderate

HMG-CoA REDUCTASE INHIBITORS ("Statins")

2 of 2

Fluvastatin also falls under HMG-CoA REDUCTASE INHIBITORS ("Statins").

Theoretically, concomitant use of niacin and statins might increase the risk of myopathy and rhabdomyolysis in some patients.
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, including those using an FDA-approved combination of lovastatin and niacin (Advicor).
Severity Moderate Likelihood Possible Evidence D

Interaction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists.

Dr. Brian Staiger, PharmD, BCPS
Dr. Brian Staiger explains PharmD, Clinical Pharmacist

Here's the gist of pairing high-dose niacin with fluvastatin (Lescol). The concern isn't that niacin changes how your body breaks fluvastatin down. Instead, both can independently stress muscle tissue, so taking them together has, in theory, been linked to a higher chance of muscle problems. The signs to watch for would be unusual muscle aches, tenderness, weakness, or dark-colored urine, which in rare cases points to a serious condition called rhabdomyolysis.

The good news: this is mostly based on scattered case reports, and large studies (including an FDA-approved niacin-statin combo) didn't show a clear jump in risk. So it's worth being aware of, not panicking over. Everyday food and a regular B3 vitamin won't be an issue. If you're considering prescription-strength niacin, just loop in your pharmacist or doctor first.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. 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
  2. Bays HE, Dujovne CA. Drug interactions of lipid-altering drugs. Drug Saf 1998;19:355-71. PubMed
  3. McKenney J. New perspectives on the use of niacin in the treatment of lipid disorders. Arch Intern Med 2004;164:697-705. PubMed
  4. Reaven P, Witztum JL. Lovastatin, nicotinic acid and rhabdomyolysis (letter). Ann Int Med 1988;109:597-8. PubMed
  5. 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
  6. Garnett WR. Interactions with hydroxymethylglutaryl-coenzyme A reductase inhibitors. Am J Health Syst Pharm. 1995;52(15):1639-45. PubMed

What These Ratings Mean

Every interaction above is graded three ways — here’s the key to each label.

Severity how clinically significant the interaction is
Major

Clinically significant. Avoid the combination, or use only under close professional supervision.

Moderate

Usually worth avoiding or managing — may need monitoring, a dose change, or timing apart.

Minor

Generally not serious. Be aware of it and mention it to your pharmacist.

Likelihood how strong the evidence is that the interaction actually happens in people
  • LikelyWell-controlled human studies have demonstrated the likely existence of this interaction.
  • ProbableInteraction has not been documented in well-controlled studies, however, the interaction has been demonstrated in some small human studies or in controlled animal studies in conjunction with multiple case reports.
  • PossibleInteraction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists.
  • UnlikelyInteraction has been demonstrated in animal or in lab research but has been shown not to occur in humans.
Evidence the quality of the studies behind the rating (graded A–D)
  • AHigh-quality meta-analysis (quantitative systematic review).
  • BCase-control study.
  • CConsensus.
  • DAnecdotal evidence.

These ratings are for information only. Never start, stop, or otherwise change your therapy before speaking with your provider.

Keep it in perspective

Niacin Also Interacts With Other Medications

Niacin has 726 moderate known drug interactions in our database — the Fluvastatin one above is among them. If you take anything else, check it against the full list below.

Moderate 726 No known interaction 2,104 (incl. Fluvastatin)
Taking anything else?

Check Another of Your Medications Against Niacin

Covers the 2,830 medications we’ve checked against Niacin. Pick one to open its full report.

Everything else you take

See Every Supplement That Interacts With Fluvastatin

This page covers Niacin only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Fluvastatin page lists 128 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Apple (major), Beer (major), Grapefruit (major) and Siberian Cocklebur (major).

By severity: 7 major · 97 moderate · 24 minor.

Open the Fluvastatin interaction page

One more smart check

Taking Niacin as Part of a Dietary Supplement Product? Check It for Interactions

We hold 933 real supplement products containing Niacin, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Niacin. Your product may carry other ingredients that interact with Fluvastatin too, on top of Niacin — and those would not show on this page. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Niacin and Fluvastatin Sit Against Everything Else

Out of every supplement and medication people look up on HelloPharmacist, here is where these two land this week — and which way each has been moving.

Supplement Niacin
Top 25%

#240 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Fluvastatin
Top half

#986 of 2,830 medications looked up here in the last 7 days

29 days ago today

Position among everything looked up on this site, not a measure of how commonly either one is used or how important it is. A supplement can climb this list because of a news story. It counts every request to the page, automated ones included, and nothing here identifies anyone.

Supplement

About Niacin

What is Niacin?

Niacin
  • High cholesterol
  • Vitamin B3 deficiency (pellagra)
  • Heart health support
  • General energy and metabolism

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 adjust cholesterol levels, but high doses can cause flushing and other side effects and should only be taken under medical supervision. Always talk with a pharmacist or doctor before using high-dose niacin supplements.

Read the full Niacin monograph & all interactions
Medication

About Fluvastatin

What Is Fluvastatin Used For?

Brand names: Lescol, Lescol XL

Fluvastatin capsules are used alongside diet to lower total cholesterol, LDL cholesterol, triglycerides, and apolipoprotein B, and to raise HDL cholesterol in adults with primary hypercholesterolemia (high cholesterol) or mixed dyslipidemia (abnormal cholesterol and triglyceride levels). Fluvastatin capsules are also used in boys and girls aged 10–16 who have heterozygous familial hypercholesterolemia (an inherited form of high cholesterol) when diet alone has not worked. In adults with clinically evident coronary heart disease (CHD), fluvastatin capsules may reduce the risk of needing a coronary revascularization procedure (a procedure to restore blood flow, such as angioplasty) and can slow the progression of coronary atherosclerosis (plaque buildup in heart arteries).

Fluvastatin sodium extended-release tablets and Lescol XL (extended-release tablet) share similar uses: reducing LDL cholesterol in adults with primary hyperlipidemia, reducing LDL in adults and children aged 10 and older with heterozygous familial hypercholesterolemia who require the highest available dose, and reducing cardiovascular risk in adults with established coronary heart disease. Fluvastatin is always used together with a cholesterol-lowering diet, not as a replacement for one.

See full Fluvastatin drug information
Keep checking

Other Drugs & Niacin

Browse every other medication we’ve checked against Niacin — both the ones with a known interaction and the ones without. Select any drug for the full detail.

0Major
726Moderate
0Minor
2,103No known interaction
726 Moderate 2,103 No interaction
Moderate

726 interactions

Showing 60 of 726 moderate interactions — see all 726 on the Niacin page.

No interaction 2,103 drugs checked — show the list

We also checked Niacin against these medications and found no known interaction in our sources. Open any page to confirm.

Showing the 60 most looked-up of 2,103 medications checked with no known interaction — see the full Niacin list.

See the full Niacin interactions page
See every supplement checked against Fluvastatin, ranked by severity
Sources

Sources & How We Checked

Interaction details are evidence-graded and sourced from the Natural Medicines database. The medication overview comes from MedlinePlus.

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

Parts of this content are provided by the Therapeutic Research Center, LLC.

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

Keep exploring
Niacin monograph › Uses, safety, and every drug interaction in one place Fluvastatin supplement interactions › Every supplement checked against Fluvastatin, ranked by severity Fluvastatin drug information › The full plain-English guide to this medication Supplement interaction checker › Check any supplement or product against your medications Browse medications A–Z › Every drug we've checked against herbs & supplements Ask a pharmacist › Free, personal answer from our licensed team
Pharmacist Counseling Corner

Taking Niacin and Fluvastatin Together: Common Questions

Can you take Niacin with Fluvastatin?
There is a moderate interaction, so it may be acceptable with monitoring or timing changes — but check with your pharmacist first. Read the full details on this page and confirm with your pharmacist before combining them.
Why are there 2 interactions listed for Niacin and Fluvastatin?
Fluvastatin belongs to more than one drug category, and Niacin interacts with each of those categories a little differently. We list every one so nothing is missed — your overall risk is driven by the most serious of them.
How serious is the Niacin and Fluvastatin interaction?
We rate it Moderate. This combination may require monitoring, a dose adjustment, or separating the times you take each one. Consult your pharmacist before using them together.

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

Still Have a Question About Fluvastatin and Niacin?

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This information is for education only and is not a substitute for professional medical advice. Always check with your pharmacist or doctor before starting, stopping, or combining supplements and medications.