Niacin + Niacin, Simvastatin
Niacin, Simvastatin brand name: Simcor.
Niacin, Simvastatin 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 reportNiacin and Niacin, Simvastatin
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. Niacin, Simvastatin 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).
HEPATOTOXIC DRUGS
1 of 2Why this applies to Niacin, Simvastatin
Niacin, Simvastatin falls under HEPATOTOXIC DRUGS — the group Niacin interacts with.
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.
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.
Here's a slightly funny twist: the product you're asking about (Simcor) already combines niacin with simvastatin in one pill. So adding a separate niacin supplement on top means you'd be stacking even more niacin onto a medicine that already contains it. The concern on file is that both niacin and statins can stress the liver, and piling on extra niacin could, in theory, raise that risk a bit more.
In real life, watch for signs your liver is unhappy: unusual tiredness, belly pain on the upper right side, dark urine, or yellowing of the skin or eyes. Also note that high-dose niacin can cause flushing and itching. This warning is theoretical, based on how these drugs behave, not strong proof. Please don't add niacin on your own. Let your pharmacist or doctor weigh in first.
- 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
- Bays HE, Dujovne CA. Drug interactions of lipid-altering drugs. Drug Saf 1998;19:355-71. PubMed
- Rader JI, Calvert RJ, Hathcock JN. Hepatic toxicity of unmodified and time-release preparations of niacin. Am J Med 1992;92:77-81. PubMed
- 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
- 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
- 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
- Bassan M. A case for immediate-release niacin. Heart Lung. 2012 Jan-Feb;41(1):95-8. PubMed
- 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
HMG-CoA REDUCTASE INHIBITORS ("Statins")
2 of 2Niacin, Simvastatin also falls under HMG-CoA REDUCTASE INHIBITORS ("Statins").
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).
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.
Here's something interesting about your situation: this product (Simcor) actually combines niacin and simvastatin in one pill on purpose, so the two are already meant to be taken together to help your cholesterol numbers. The concern on file is that, in theory, pairing niacin with a statin like simvastatin might raise the small chance of muscle problems. We're talking about unexplained muscle aches, weakness, or tenderness, and rarely a more serious muscle breakdown called rhabdomyolysis.
I want to be honest about the evidence, though: this worry comes mostly from a handful of case reports, and big studies haven't actually shown a clear jump in muscle risk. So don't panic. Just let your pharmacist or doctor know right away if you notice new muscle pain or dark urine, and don't change your dose on your own.
- 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
- Bays HE, Dujovne CA. Drug interactions of lipid-altering drugs. Drug Saf 1998;19:355-71. PubMed
- McKenney J. New perspectives on the use of niacin in the treatment of lipid disorders. Arch Intern Med 2004;164:697-705. PubMed
- Reaven P, Witztum JL. Lovastatin, nicotinic acid and rhabdomyolysis (letter). Ann Int Med 1988;109:597-8. PubMed
- 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
- 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.
Clinically significant. Avoid the combination, or use only under close professional supervision.
Usually worth avoiding or managing — may need monitoring, a dose change, or timing apart.
Generally not serious. Be aware of it and mention it to your pharmacist.
- 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.
- 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.
Niacin Also Interacts With Other Medications
Niacin has 726 moderate known drug interactions in our database — the Niacin, Simvastatin one above is among them. If you take anything else, check it against the full list below.
Check Another of Your Medications Against Niacin
We haven’t checked that one against Niacin yet — ask our pharmacists directly.
Covers the 2,830 medications we’ve checked against Niacin. Pick one to open its full report.
See Every Supplement That Interacts With Niacin, Simvastatin
This page covers Niacin only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Niacin, Simvastatin page lists 187 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: 8 major · 140 moderate · 39 minor.
From our pharmacist’s overview on the Niacin, Simvastatin page
“Simcor combines niacin with simvastatin to lower cholesterol, and its interaction list deserves genuine care. Simvastatin is cleared by the CYP3A4 enzyme, and well over a hundred of these ingredients can push its blood level up or drag it down through that pathway.”
Reviewed by 2 · Jul 18, 2026
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 Niacin, Simvastatin 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:
Where Niacin and Niacin, Simvastatin 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.
#224 of 1,452 supplements looked up here in the last 7 days
#1,048 of 2,830 medications looked up here in the last 7 days
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.
About Niacin
What is 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.
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.
No drugs match “”.
726 interactions
- Diclofenac Sodium ›
- Diltiazem ›
- Nifedipine ›
- Ibuprofen ›
- Aspirin ›
- Insulin (rdna) ›
- Naproxen ›
- Doxycycline ›
- Minocycline ›
- Propranolol ›
- Tetracycline ›
- Levothyroxine ›
- Amoxicillin ›
- Hydrochlorothiazide ›
- Testosterone ›
- Verapamil ›
- Fenofibrate ›
- Levonorgestrel ›
- Quinidine ›
- Cyclosporine ›
- Glyburide ›
- Insulin (pork) ›
- Methyltestosterone ›
- Ciprofloxacin ›
- Nicotine ›
- Phenytoin ›
- Allopurinol ›
- Carbamazepine ›
- Diclofenac Potassium ›
- Dipyridamole ›
- Hydralazine ›
- Insulin (human) ›
- Acetaminophen ›
- Conjugated Estrogens ›
- Ketoprofen ›
- Methotrexate ›
- Nitrofurantoin ›
- Ofloxacin ›
- Propoxyphene ›
- Rifampin ›
- Testosterone Undecanoate ›
- Trichlormethiazide ›
- Acarbose ›
- Bendroflumethiazide ›
- Bivalirudin ›
- Dapsone ›
- Doxycycline Hyclate ›
- Duloxetine ›
- Eltrombopag ›
- Insulin Glargine ›
- Interferon Alfa-2b ›
- Interferon Beta-1b ›
- Isoniazid ›
- Itraconazole ›
- Levofloxacin ›
- Levothyroxine Sodium ›
- Liotrix ›
- Lisinopril ›
- Metolazone ›
- Minoxidil ›
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.
- Methylphenidate ›
- Sertraline ›
- Ivermectin ›
- Escitalopram ›
- Tadalafil ›
- Abemaciclib ›
- Docusate ›
- Valacyclovir ›
- Hydroxyurea ›
- Methamphetamine ›
- Sumatriptan ›
- Prednisone ›
- Lisdexamfetamine ›
- Bupropion ›
- Bendamustine ›
- Amitriptyline ›
- Acyclovir ›
- Fluoxetine ›
- Amphetamine ›
- Lamotrigine ›
- Pregabalin ›
- Azithromycin ›
- Gabapentin ›
- Dextroamphetamine ›
- Isotretinoin ›
- Clonazepam ›
- Methylene Blue ›
- Omeprazole ›
- Quetiapine ›
- Letrozole ›
- Buspirone ›
- Citalopram ›
- Diazepam ›
- Cephalexin ›
- Cyclopentolate ›
- Acetaminophen, Dextromethorphan, Doxylamine ›
- Roxithromycin ›
- Pegunigalsidase Alfa-iwxj ›
- Levetiracetam ›
- Finasteride ›
- Mirtazapine ›
- Estrogen ›
- Daptomycin ›
- Ezetimibe ›
- Dexmethylphenidate ›
- Hexobarbitone ›
- Phentermine, Topiramate ›
- Carbidopa, Levodopa ›
- Alprazolam ›
- Factor 7a ›
- Bromocriptine ›
- Aripiprazole ›
- Dutasteride ›
- Levodopa ›
- Finasteride, Tadalafil ›
- Mitomycin ›
- Hethylphenidate Hcl ›
- Cefaclor ›
- Venlafaxine ›
- Azelaic Acid ›
Showing the 60 most looked-up of 2,103 medications checked with no known interaction — see the full Niacin list.
Sources & How We Checked
Interaction details are evidence-graded and sourced from the Natural Medicines database. The medication overview comes from MedlinePlus.
- Natural Medicines (Therapeutic Research Center) — Evidence-graded clinical reference for vitamins, herbs and supplements — the basis for our interaction data.
- MedlinePlus, U.S. National Library of Medicine — NIH consumer drug information, used for the medication overviews.
- NIH Dietary Supplement Label Database (DSLD) — Official supplement product labels.
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
Niacin, Simvastatin Is Linked to Lower Levels of 3 Nutrients
Natural Medicines records Niacin, Simvastatin as a medicine that can lower these. This is not an interaction with Niacin — it is a separate effect of the medicine, and it is a reason some people are advised to supplement rather than to avoid one:
Read the full Niacin, Simvastatin nutrient depletion report ›
Niacin is itself a nutrient we track — see which medications may deplete NIACIN.
Depletion records come from the licensed Natural Medicines database. Do not start a supplement on the strength of this page — ask your pharmacist or doctor whether it applies to you.
Taking Niacin and Niacin, Simvastatin Together: Common Questions
Can you take Niacin with Niacin, Simvastatin?
Why are there 2 interactions listed for Niacin and Niacin, Simvastatin?
How serious is the Niacin and Niacin, Simvastatin interaction?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
Still Have a Question About Niacin, Simvastatin 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.