Niacin and Lovastatin: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Niacin
Lovastatin
How we grade severity & evidence
Severity levels
- Contraindicated: These should generally not be used together.
- Major: Potentially serious — often needs a change or close monitoring.
- Moderate: Can be significant — usually manageable with monitoring.
- Minor: Usually limited clinical impact.
Evidence grades
- Established: Well documented — supported by controlled studies or strong clinical data.
- Probable: Good supporting evidence, though not definitively proven.
- Suspected: Some evidence suggests this interaction, but it is not well established.
- Possible: Limited or conflicting evidence; the interaction may occur.
- Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.
Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.
What happens
Increased risk of myopathy or rhabdomyolysis
Interaction Deep Dive
The concurrent use of lovastatin and niacin in lipid-lowering doses (greater than 1 gram daily) has resulted in reversible myopathy and rhabdomyolysis1237. However, two short-term studies have found that the combination of low-dose lovastatin plus niacin resulted in no reports of myopathy or rhabdomyolysis 56. Use caution with the concomitant use of both drugs. Monitor the patient for signs and symptoms of myopathy or rhabdomyolysis (muscle pain, tenderness, or weakness); consider periodic monitoring of creatine kinase (CK) levels. Discontinue lovastatin if CK levels are markedly elevated or if myopathy or rhabdomyolysis is diagnosed or suspected 4.
Why it happens (mechanism)
Unknown
Literature reports
2 reports — tap to read
a) A clinical trial involving 25 hyperlipidemic patients found no serious side effects and no statistically significant difference in adverse events reported between patients treated with placebo compared to patients receiving the combination of 1.2 g sustained-release nicotinic acid and 20 mg lovastatin. Subjects were randomized to a treatment sequence: three months of nicotinic acid plus placebo; three months of lovastatin plus placebo; and three months of nicotinic acid plus lovastatin, with each treatment period separated by a 2-month placebo washout. There were no statistically significant changes in hepatic or muscle enzyme serum tests. The authors noted that slow-release nicotinic acid may be associated with a risk of hepatotoxicity, and, therefore, the immediate-release form should now be used instead 5.
b) A short-term prospective, randomized clinical trial found little or no change in liver function tests, glucose, or uric acid levels following treatment with a combination of lovastatin 20 mg daily with niacin 1.5 grams daily. Thirty-two subjects with low-density lipoprotein (LDL) levels over 130 mg/deciliter were randomly assigned to six weeks of either monotherapy with 40 mg of lovastatin every evening, or combination therapy with lovastatin 20 mg daily and niacin 500 mg three times daily. One patient experienced joint discomfort and a rise in uric acid, and consequently was advised to discontinue the niacin. Otherwise, the regimen was well-tolerated. The authors caution that more side effects may occur with longer therapy 6.
Common questions
Can I take Niacin and Lovastatin together?
Increased risk of myopathy or rhabdomyolysis Always confirm with your pharmacist or prescriber before making any change.
How serious is the Niacin and Lovastatin interaction?
It is rated major. Potentially serious — often needs a change or close monitoring.
How quickly could this interaction happen?
The documented onset is "delayed". Effects tend to build up gradually over days to weeks.
How strong is the evidence for this interaction?
The evidence is graded "probable". Good supporting evidence, though not definitively proven.
Questions for your pharmacist
- Does my dose of Niacin or Lovastatin need adjusting while I take them together?
- What symptoms should prompt me to call you or my prescriber right away?
- Does the timing of my doses matter for this combination?
- Is there a safer alternative to one of these medications for me?
References (7)
- Malloy MJ, Kane JP, Kunitake ST, et al: Complementarity of colestipol, niacin, and lovastatin in treatment of severe familial hypercholesterolemia. Ann Intern Med 1987; 107(5):616-623. PubMed
- Reaven P & Witztum JL: Lovastatin, nicotinic acid, and rhabdomyolysis (letter). Ann Intern Med 1988; 109:597-598. DOI
- Norman DJ, Illingworth DR, Munson J, et al: Myolysis and acute renal failure in heart-transplant recipient receiving lovastatin (letter). N Engl J Med 1988; 318:46.
- Product Information: MEVACOR(R) oral tablets, lovastatin oral tablets. Merck & Co, Inc. (Per FDA), Whitehouse Station, NJ, 2012. DailyMed
- Vacek JL, Dittmeier G, Chiarelli T, et al: Comparison of lovastatin (20mg) and nicotinic acid (1.2 g) with either drug alone for type II hyperlipoproteinemia. Am J Cardiol 1995; 76:182-184.
- Gardner SF, Schneider EF, Granberry MC, et al: Combination therapy with low-dose lovastatin and niacin is as effective as higher-dose lovastatin. Pharmacotherapy 1996; 16:419-423. DOI
- Cooke HM: Lovastatin- and niacin-induced rhabdomyolysis. Hosp Pharm 1994; 29:33-34.
Keep reading about Niacin
Keep reading about Lovastatin
These medications also interact with supplements
Prescription drugs aren't the whole picture — herbal and dietary supplements can interact with them too. From the evidence-graded Natural Medicines database:
major · moderate · minor — check everything you take with our drug–supplement interaction checker.
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