Drug & supplement interaction

Red Yeast Rice + Acyclovir

Acyclovir brand names: Zovirax, Zovirax Injection, Sitavig, Avaclyr.

No Known Interaction

Medically reviewed by Dr. Brian Staiger, PharmD, BCPS · Updated July 2026 · Pair last verified Sep 13, 2026

The bottom line No known interaction

We found no known interaction between Red Yeast Rice and Acyclovir in our sources. Absence of a documented interaction is not the same as proven safety, and does not guarantee one does not exist. Do not start, stop, or change a medication or supplement based on this page; confirm with your pharmacist or doctor first. Additionally, although there is no interaction, the two are separately associated with some of the same side effects, which would make a new symptom harder to attribute to one or the other.

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Interaction report

Red Yeast Rice and Acyclovir

We checked these two against our interaction database. Here is what we found.

No Known Interaction Found

We did not find a documented interaction between Acyclovir and Red Yeast Rice in our sources. This does not guarantee that the combination is completely free of risk — there is often limited research on supplements and herbal products, especially around drug interactions.

If you decide to take both, the practical routine is simple: add one new thing at a time and note the date you started it. If the combination is going to disagree with you, it usually shows in the first days to a couple of weeks — and a start date turns “I’ve been feeling off” into something a pharmacist can actually work with. Do not stop a prescribed medicine on your own.

Always talk with your pharmacist or doctor before making changes to your medications or supplements, particularly if you take several medications or have an ongoing health condition.

Red Yeast Rice safety at a glance

Red Yeast Rice overall Use caution It works like a statin drug and can carry similar risks, plus product quality varies.

Pregnancy Likely Unsafe When used orally. The red yeast rice constituent, lovastatin, has induced fetal skeletal malformations in animals. The US Food and Drug Administration (FDA) rec... Read the full pregnancy detail

Breastfeeding Avoid Avoid because of its statin-like activity and lack of safety data.

Pregnancy & breastfeeding ratings are from Natural Medicines (Therapeutic Research Center) — the full detail is in the Special populations card below. Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Acyclovir and Red Yeast Rice? Ask Dr. Brian Staiger, PharmD, BCPS directly ›

How we checked

Why No Interaction Is Listed for Acyclovir

Interactions in our licensed database are recorded against drug classes, not just single drug names. Acyclovir is filed under 6 classifications — including organic anion transporter 1 (oat1) substrates, topical drugs, nephrotoxic drugs. Red Yeast Rice has documented interactions with 6 drug classes — the most serious being cyclosporine (neoral, sandimmune) (moderate), cytochrome p450 3a4 (cyp3a4) inhibitors (moderate) and gemfibrozil (lopid) (moderate) — and none of Acyclovir’s classifications are among them.

Classification data comes from our licensed Natural Medicines dataset. A medication can belong to classes beyond those recorded there, so this describes how the check was run — it is not a safety guarantee.

Keep it in perspective

Red Yeast Rice Does Interact With Other Medications

Red Yeast Rice has 477 moderate known drug interactions in our database — Acyclovir isn’t one of them. If you take anything else, check it against the full list below.

Moderate 477 No known interaction 2,353 (incl. Acyclovir)

Taking anything else?

Check Another of Your Medications Against Red Yeast Rice

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

What to actually watch for

No Interaction Found — But Data Suggests Red Yeast Rice and Acyclovir May Share Several of the Same Side Effects

This is not an interaction. Neither one changes how your body handles the other, and nothing here says they react together. What our sources do show is that each has separately been linked to the effects below — so taking both can make those effects more likely to turn up, and harder to pin on one or the other if they do. One of them is worth acting on rather than waiting out — marked below.

Kidney problems Worth acting on Additional detail
Red Yeast Rice
“Orally, contaminated red yeast rice may cause renal toxicity. Analyses of red yeast rice products have found that about one-third to two-thirds of these products contain citrinin, a mold toxin that results from incorrect rice fermentation processes.”

Red Yeast Rice · Natural Medicines adverse-effect record, reported in fanconi syndrome.
6 sources cited

9588. Heber D, Lembertas A, Lu QY, et al. An analysis of nine proprietary Chinese red yeast rice dietary supplements: implications of variability in chemical profile and contents. J Altern Complement Med 2001;7:133-9. PubMed

17501. Gordon RY, Cooperman T, Obermeyer W, Becker DJ. Marked variability of monacolin levels in commercial red yeast rice products: buyer beware! Arch Intern Med 2010;170:1722-7. PubMed

70543. Blanc PJ, Laussac JP, Le Bars J, et al. Characterization of monascidin A from Monascus as citrinin. Int J Food Microbiol. 1995;27(2-3):201-213. PubMed

95666. Gerards MC, Terlou RJ, Yu H, Koks CH, Gerdes VE. Traditional Chinese lipid-lowering agent red yeast rice results in significant LDL reduction but safety is uncertain - a systematic review and meta-analysis. Atherosclerosis. 2015;240(2):415-23. doi: 10.101 PubMed

70482. Liu, B. H., Wu, T. S., Su, M. C., Chung, C. P., and Yu, F. Y. Evaluation of citrinin occurrence and cytotoxicity in Monascus fermentation products. J Agric.Food Chem. 1-12-2005;53(1):170-175.

70540. Chagas, G. M., Kluppel, M. L., Campello, Ade P., Buchi, Dde F., and de Oliveira, M. B. Alterations induced by citrinin in cultured kidney cells. Cell Struct.Funct. 1994;19(2):103-108. PubMed
Acyclovir

Listed in the ADVERSE REACTIONS section of the FDA label for Acyclovir. Read the label on DailyMed ›
Tiredness reported in 7.0% of FDA reports for Acyclovir Additional detail
Red Yeast Rice
“Orally, red yeast rice has been associated with dizziness, headache, fatigue, and tingling in the extremities. A case of peripheral neuropathy occurred in a 60-year-old male with a gastrointestinal tumor who was taking imatinib 400 mg daily along with red yeast rice for 3 years. Three months after cessation of red yeast rice, symptoms resolved.”

Red Yeast Rice · Natural Medicines adverse-effect record, reported in cluster headache.
6 sources cited

6988. Wang J, Lu A, Chi J. Multicenter clinical trial of the serum lipid-lowering effects of a monascus purpureus (red yeast) rice preparation from traditional Chinese medicine. Cur Ther Res 1997;58:964-78. DOI

16836. Becker DJ, Gordon RY, Halbert SC, et al. Red yeast rice for dyslipidemia in statin-intolerant patients: A randomized trial. Ann Intern Med 2009;150:830-9. PubMed

17089. Halbert SC, French B, Gordon RY, et al. Tolerability of red yeast rice (2,400 mg twice daily) versus pravastatin (20 mg twice daily) in patients with previous statin intolerance. Am J Cardiol 2010;105:198-204. PubMed

18110. Karl M, Rubenstein M, Rudnick C, Brejda J. A multicenter study of nutraceutical drinks for cholesterol (evaluating effectiveness and tolerability). J Clin Lipidology 2012;6:150-158. PubMed

94001. Mazzanti G, Moro PA, Raschi E, Da Cas R, Menniti-Ippolito F. Adverse reactions to dietary supplements containing red yeast rice: assessment of cases from the Italian surveillance system. Br J Clin Pharmacol 2017;83(4):894-908. PubMed

114649. Trogkanis E, Karalexi MA, Sergentanis TN, Kornarou E, Vassilakou T. Safety and Efficacy of the Consumption of the Nutraceutical "Red Yeast Rice Extract" for the Reduction of Hypercholesterolemia in Humans: A Systematic Review and Meta-Analysis. Nutrients PubMed
Acyclovir

Listed in the ADVERSE REACTIONS section of the FDA label for Acyclovir, and in voluntary FDA adverse-event reports. Read the label on DailyMed ›
A skin rash reported in 3.7% of FDA reports for Acyclovir Additional detail
Red Yeast Rice
“Orally, red yeast rice has been rarely associated with mild cases of pruritus and rash in clinical trials and post marketing surveillance. Two cases of alopecia were reported in patients taking red yeast rice in clinical research.”

Red Yeast Rice · Natural Medicines adverse-effect record, reported in alopecia.
4 sources cited

70531. Liu, Z. L., Liu, J. P., Zhang, A. L., Wu, Q., Ruan, Y., Lewith, G., and Visconte, D. Chinese herbal medicines for hypercholesterolemia. Cochrane Database Syst Rev 2011;(7):CD008305. PubMed

94001. Mazzanti G, Moro PA, Raschi E, Da Cas R, Menniti-Ippolito F. Adverse reactions to dietary supplements containing red yeast rice: assessment of cases from the Italian surveillance system. Br J Clin Pharmacol 2017;83(4):894-908. PubMed

114649. Trogkanis E, Karalexi MA, Sergentanis TN, Kornarou E, Vassilakou T. Safety and Efficacy of the Consumption of the Nutraceutical "Red Yeast Rice Extract" for the Reduction of Hypercholesterolemia in Humans: A Systematic Review and Meta-Analysis. Nutrients PubMed

17089. Halbert SC, French B, Gordon RY, et al. Tolerability of red yeast rice (2,400 mg twice daily) versus pravastatin (20 mg twice daily) in patients with previous statin intolerance. Am J Cardiol 2010;105:198-204. PubMed
Acyclovir

Listed in the ADVERSE REACTIONS section of the FDA label for Acyclovir, and in voluntary FDA adverse-event reports. Read the label on DailyMed ›
Dizziness / Headache Additional detail

Red Yeast Rice

Recorded for Red Yeast Rice in the same Natural Medicines adverse-effect record shown under Kidney problems above.

Acyclovir

Listed in the ADVERSE REACTIONS section of the FDA label for Acyclovir. Read the label on DailyMed ›
Nausea reported in 4.9% of FDA reports for Acyclovir Additional detail
Red Yeast Rice
“Orally, red yeast rice has been associated with mild adverse effects including abdominal discomfort, bloating, heartburn, flatulence, diarrhea or loose stools, nausea, vomiting, abdominal distention or pain, and reduced appetite, in clinical trials and post marketing surveillance. Taking red yeast rice with food may reduce the risk of heartburn, gas, and abdominal discomfort.”

Red Yeast Rice · Natural Medicines adverse-effect record, reported in diarrhea.
6 sources cited

2624. Heber D, Yip I, Ashley JM, et al. Cholesterol-lowering effects of a proprietary Chinese red-yeast-rice dietary supplement. Am J Clin Nutr 1999;69:231-6. PubMed

6988. Wang J, Lu A, Chi J. Multicenter clinical trial of the serum lipid-lowering effects of a monascus purpureus (red yeast) rice preparation from traditional Chinese medicine. Cur Ther Res 1997;58:964-78. DOI

16836. Becker DJ, Gordon RY, Halbert SC, et al. Red yeast rice for dyslipidemia in statin-intolerant patients: A randomized trial. Ann Intern Med 2009;150:830-9. PubMed

70556. Bonovich, K., Colfer, H., Petoskey, M. I., and et al. A multi-center, self-controlled study of cholestin in subjects with elevated cholesterol. Journal of Investigative Medicine 1999;47(2):54A.

94001. Mazzanti G, Moro PA, Raschi E, Da Cas R, Menniti-Ippolito F. Adverse reactions to dietary supplements containing red yeast rice: assessment of cases from the Italian surveillance system. Br J Clin Pharmacol 2017;83(4):894-908. PubMed

114649. Trogkanis E, Karalexi MA, Sergentanis TN, Kornarou E, Vassilakou T. Safety and Efficacy of the Consumption of the Nutraceutical "Red Yeast Rice Extract" for the Reduction of Hypercholesterolemia in Humans: A Systematic Review and Meta-Analysis. Nutrients PubMed
Acyclovir

Listed in the ADVERSE REACTIONS section of the FDA label for Acyclovir, and in voluntary FDA adverse-event reports. Read the label on DailyMed ›
Vomiting Additional detail

Red Yeast Rice

Recorded for Red Yeast Rice in the same Natural Medicines adverse-effect record shown under Nausea above.

Acyclovir

Listed in the ADVERSE REACTIONS section of the FDA label for Acyclovir. Read the label on DailyMed ›

Reported for Red Yeast Rice but not commonly for Acyclovir: liver problems, numbness or tingling, stomach upset and erection problems.

Effects for Acyclovir come from the ADVERSE REACTIONS section of its FDA label; effects for Red Yeast Rice come from the Natural Medicines adverse-effect record, quoted above. Where a percentage is shown, it is the share of 114,761 voluntary FDA FAERS reports for Acyclovir that mention that effect — a reporting proportion, not an incidence rate and not evidence the drug caused it. Wording is matched across sources by our own clinical vocabulary, so treat this as a prompt to pay attention, not a diagnosis.

Special populations

Red Yeast Rice in Pregnancy & Breastfeeding

Pregnancy Likely Unsafe

When used orally. The red yeast rice constituent, lovastatin, has induced fetal skeletal malformations in animals. The US Food and Drug Administration (FDA) recommends that most patients discontinue statin therapy during pregnancy due to the risks to the fetus; however, in certain high-risk patients, a prescription statin may be continued during pregnancy.

DISCLAIMER: This tool is intended for informational purposes only, and should not be interpreted as specific medical advice. Patients should consult with a qualified healthcare provider before making decisions about therapies and/or health conditions.© 2026 Therapeutic Research Center

From our Q&A

Questions About Red Yeast Rice or Acyclovir

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Red Yeast Rice or Acyclovir, not necessarily both, but if one is close to what you were about to ask it will usually go further than a database entry can:

Not quite your question? Ask our pharmacists directly — it is free, there is no account required, and answers usually come back within 24 hours.

Everything else you take

See Every Supplement That Interacts With Acyclovir

This page covers Red Yeast Rice only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Acyclovir page lists 37 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Asarabacca (major), Siberian Cocklebur (major), African Wild Potato (moderate) and Aristolochia (moderate).

By severity: 3 major · 23 moderate · 11 minor.

From our pharmacist’s overview on the Acyclovir page

“Kidney strain is the risk to understand first. Acyclovir (Zovirax) can stress the kidneys on its own, and a few ingredients here, Siberian cocklebur especially, are toxic to kidney tissue, so pairing them could compound the harm.”

Reviewed by 2 · Jul 18, 2026

Open the Acyclovir interaction page

One more smart check

Taking Red Yeast Rice as Part of a Dietary Supplement Product? Check It for Interactions

We hold 593 real supplement products containing Red Yeast Rice, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Red Yeast Rice. Even though Red Yeast Rice itself has no known interaction with Acyclovir, another ingredient on your label might. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Red Yeast Rice and Acyclovir 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 Red Yeast Rice

Top 25%

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

29 days ago today

Medication Acyclovir

Top 5%

#59 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.

Where does our data come from?

Source: the Natural Medicines (TRC Healthcare) clinical database — the evidence-graded professional reference for herb & supplement interactions.
Citation library: 103,510 references behind our interaction content, 65,311 of them resolved to verified PubMed/DOI sources. See every Red Yeast Rice reference on this page ↓
Freshness: we automatically re-check this combination every week — this pair was last verified September 13, 2026. The Red Yeast Rice and Acyclovir records this page draws on were last updated July 11, 2026.
What “no known interaction” means: no documented interaction in the sources above — not a guarantee of safety. Supplements are studied far less than prescription drugs, so we say exactly what the evidence supports, and nothing more.

Data structure & sourcing designed and verified by Dr. Brian Staiger, PharmD, BCPS.

Supplement

About Red Yeast Rice

What is Red Yeast Rice?

High cholesterol
Heart health
Metabolic syndrome
Statin alternative

Red yeast rice contains monacolin K, which is chemically identical to the prescription statin lovastatin, and it can lower LDL ('bad') cholesterol. Because of this, it carries the same risks as statin drugs, and the amount of active ingredient varies widely between products. Always talk to your pharmacist or doctor before using it, especially if you have liver problems or take other medicines.

Monascus purpureus · Rice fermented with Monascus purpureus yeast · Capsules, tablets, powder

An interaction check asks whether these two react with each other — it does not ask whether Red Yeast Rice is a good idea for someone in your situation. Here is what our Red Yeast Rice record says about it on its own.

Red Yeast Rice: dosing

There is no official standardized dose for red yeast rice, and the amount of active monacolin K varies a lot between products. This makes it hard to know exactly how much you are getting.The safest approach is to follow the directions on the product label and to choose products that are independently tested for purity and citrinin contamination.

From our Red Yeast Rice monograph — the full record covers uses, side effects and every documented interaction.

Read the full Red Yeast Rice monograph & all interactions

Medication

About Acyclovir

What Is Acyclovir Used For?

Brand names: Zovirax, Zovirax Injection, Sitavig, Avaclyr

Acyclovir treats infections caused by herpes viruses. Depending on the form, it is used for cold sores (herpes labialis), genital herpes (initial episodes and recurrent flare-ups), shingles (herpes zoster), and chickenpox (varicella). It can also be used long-term to suppress recurrent genital herpes outbreaks.

Some forms are approved for more serious situations: acyclovir injection is used in hospital settings for herpes simplex encephalitis (herpes infection of the brain), neonatal herpes (in newborns), and herpes or shingles infections in immunocompromised patients. Avaclyr ophthalmic ointment is specifically indicated for acute herpetic keratitis (a herpes ulcer on the cornea of the eye). Sitavig buccal tablet and Zovirax cream are specifically indicated for recurrent cold sores in immunocompetent adults.

Most-Reported Side Effects for Acyclovir

From FAERS, the FDA’s public side-effect reporting system (114,761 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Fatigue 8,029 reports

Diarrhea 7,348 reports

Pneumonia 5,700 reports

Nausea 5,643 reports

Fever 4,989 reports

See full Acyclovir drug information

Keep checking

Other Drugs & Red Yeast Rice

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

0Major

477Moderate

0Minor

2,352No known interaction

477 Moderate 2,352 No interaction

Moderate

477 interactions

Showing 60 of 477 moderate interactions — see all 477 on the Red Yeast Rice page.

No interaction 2,352 drugs checked — show the list

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

Showing the 60 most looked-up of 2,352 medications checked with no known interaction — see the full Red Yeast Rice list.

See the full Red Yeast Rice interactions page

See every supplement checked against Acyclovir, ranked by severity

Evidence & sources

Red Yeast Rice References

The 50 references that drive our Red Yeast Rice monograph and interaction data, from the evidence-graded Natural Medicines (TRC Healthcare) database. Citations with a link open the study on PubMed or the publisher’s site.

Hebel SK, ed. Drug Facts and Comparisons. 52nd ed. St. Louis: Facts and Comparisons, 1998.
Heber D, Yip I, Ashley JM, et al. Cholesterol-lowering effects of a proprietary Chinese red-yeast-rice dietary supplement. Am J Clin Nutr 1999;69:231-6. PubMed
Wang J, Lu A, Chi J. Multicenter clinical trial of the serum lipid-lowering effects of a monascus purpureus (red yeast) rice preparation from traditional Chinese medicine. Cur Ther Res 1997;58:964-78. DOI
Wigger-Alberti W, Bauer A, Hipler UC, Elsner P. Anaphylaxis due to Monascus purpureus-fermented rice (red yeast rice). Allergy 1999;54:1330-1.
Prasad GV, Wong T, Meliton G, Bhaloo S. Rhabdomyolysis due to red yeast rice (Monascus purpureus) in a renal transplant recipient. Transplantation 2002;74:1200-1. PubMed
Heber D, Lembertas A, Lu QY, et al. An analysis of nine proprietary Chinese red yeast rice dietary supplements: implications of variability in chemical profile and contents. J Altern Complement Med 2001;7:133-9. PubMed
Mueller PS. Symptomatic myopathy due to red yeast rice. Ann Intern Med 2006;145:474-5. PubMed
Roselle H, Ekatan A, Tzeng J, et al. Symptomatic hepatitis associated with the use of herbal red yeast rice. Ann Intern Med 2008;149:516-7. PubMed
Lapi F, Gallo E, Bernasconi S, et al. Myopathies associated with red yeast rice and liquorice: spontaneous reports from the Italian Surveillance System of Natural Health Products. Br J Clin Pharmacol 2008;66:572-74. PubMed
Becker DJ, Gordon RY, Halbert SC, et al. Red yeast rice for dyslipidemia in statin-intolerant patients: A randomized trial. Ann Intern Med 2009;150:830-9. PubMed
Halbert SC, French B, Gordon RY, et al. Tolerability of red yeast rice (2,400 mg twice daily) versus pravastatin (20 mg twice daily) in patients with previous statin intolerance. Am J Cardiol 2010;105:198-204. PubMed
Gordon RY, Cooperman T, Obermeyer W, Becker DJ. Marked variability of monacolin levels in commercial red yeast rice products: buyer beware! Arch Intern Med 2010;170:1722-7. PubMed
Karl M, Rubenstein M, Rudnick C, Brejda J. A multicenter study of nutraceutical drinks for cholesterol (evaluating effectiveness and tolerability). J Clin Lipidology 2012;6:150-158. PubMed
Huang, J., Frohlich, J., and Ignaszewski, A. P. The impact of dietary changes and dietary supplements on lipid profile. Can J Cardiol 2011;27(4):488-505. PubMed
Grieco, A., Miele, L., Pompili, M., Biolato, M., Vecchio, F. M., Grattagliano, I., and Gasbarrini, G. Acute hepatitis caused by a natural lipid-lowering product: when "alternative" medicine is no "alternative" at all. J Hepatol 2009;50(6):1273-1277. PubMed
Smith, D. J. and Olive, K. E. Chinese red rice-induced myopathy. South.Med J 2003;96(12):1265-1267. PubMed
Liu, B. H., Wu, T. S., Su, M. C., Chung, C. P., and Yu, F. Y. Evaluation of citrinin occurrence and cytotoxicity in Monascus fermentation products. J Agric.Food Chem. 1-12-2005;53(1):170-175.
Lin, C. C., Li, T. C., and Lai, M. M. Efficacy and safety of Monascus purpureus Went rice in subjects with hyperlipidemia. Eur J Endocrinol 2005;153(5):679-686. PubMed
Zhao, S. P., Lu, Z. L., Du, B. M., Chen, Z., Wu, Y. F., Yu, X. H., Zhao, Y. C., Liu, L., Ye, H. J., and Wu, Z. H. Xuezhikang, an extract of cholestin, reduces cardiovascular events in type 2 diabetes patients with coronary heart disease: subgroup analysis
Lu, Z., Kou, W., Du, B., Wu, Y., Zhao, S., Brusco, O. A., Morgan, J. M., Capuzzi, D. M., and Li, S. Effect of Xuezhikang, an extract from red yeast Chinese rice, on coronary events in a Chinese population with previous myocardial infarction. Am J Cardiol PubMed
Li, J. J., Lu, Z. L., Kou, W. R., Chen, Z., Wu, Y. F., Yu, X. H., and Zhao, Y. C. Beneficial impact of Xuezhikang on cardiovascular events and mortality in elderly hypertensive patients with previous myocardial infarction from the China Coronary Secondary
Li, J. J., Lu, Z. L., Kou, W. R., Chen, Z., Wu, Y. F., Yu, X. H., and Zhao, Y. C. Impact of Xuezhikang on coronary events in hypertensive patients with previous myocardial infarction from the China Coronary Secondary Prevention Study (CCSPS). Ann Med 2010 PubMed
Li, J. J., Lu, Z. L., Kou, W. R., Chen, Z., Wu, Y. F., Yu, X. H., and Zhao, Y. C. Long-term effects of Xuezhikang on blood pressure in hypertensive patients with previous myocardial infarction: data from the Chinese Coronary Secondary Prevention Study (CC
Liu, Z. L., Liu, J. P., Zhang, A. L., Wu, Q., Ruan, Y., Lewith, G., and Visconte, D. Chinese herbal medicines for hypercholesterolemia. Cochrane Database Syst Rev 2011;(7):CD008305. PubMed
Chagas, G. M., Kluppel, M. L., Campello, Ade P., Buchi, Dde F., and de Oliveira, M. B. Alterations induced by citrinin in cultured kidney cells. Cell Struct.Funct. 1994;19(2):103-108. PubMed
Krejci, M. E., Bretz, N. S., and Koechel, D. A. Citrinin produces acute adverse changes in renal function and ultrastructure in pentobarbital-anesthetized dogs without concomitant reductions in [potassium] plasma. Toxicology 1-8-1996;106(1-3):167-177. PubMed
Blanc PJ, Laussac JP, Le Bars J, et al. Characterization of monascidin A from Monascus as citrinin. Int J Food Microbiol. 1995;27(2-3):201-213. PubMed
Lu, Z. L., Xu, S., and Kou, W. R. The clinical observation of treatment of hyperlipidemia with different dose of Xuezhikang. National Symposium of Clinical Therapies for Cardiovascular Diseases 1995;1997:53-57.
Bonovich, K., Colfer, H., Petoskey, M. I., and et al. A multi-center, self-controlled study of cholestin in subjects with elevated cholesterol. Journal of Investigative Medicine 1999;47(2):54A.
Pisciotta, L., Boscarini, M., and Corio, R. Studi clinici su Normolip5, integratore alimentare per il controllo del colesterolo. Medicina Naturale 2004;68-70.
Barrat E, Zaïr Y, Sirvent P, et al. Effect on LDL-cholesterol of a large dose of a dietary supplement with plant extracts in subjects with untreated moderate hypercholesterolaemia: a randomised, double-blind, placebo-controlled study. Eur J Nutr. 2013;52( PubMed
Kumari S, Sherriff JM, Spooner D, Beckett R. Peripheral neuropathy induced by red yeast rice in a patient with a known small bowel gastrointestinal tumour. BMJ Case Rep. 2013;2013. PubMed
Mazzanti G, Moro PA, Raschi E, Da Cas R, Menniti-Ippolito F. Adverse reactions to dietary supplements containing red yeast rice: assessment of cases from the Italian surveillance system. Br J Clin Pharmacol 2017;83(4):894-908. PubMed
Gerards MC, Terlou RJ, Yu H, Koks CH, Gerdes VE. Traditional Chinese lipid-lowering agent red yeast rice results in significant LDL reduction but safety is uncertain - a systematic review and meta-analysis. Atherosclerosis. 2015;240(2):415-23. doi: 10.101 PubMed
Venhuis BJ, van Hunsel F, van de Koppel S, Keizers PH, Jeurissen SM, De Kaste D. Pharmacologically effective red yeast rice preparations marketed as dietary supplements illustrated by a case report. Drug Test Anal. 2016;8(3-4):315-8. doi: 10.1002/dta.1929 PubMed
Raschi E, Girardi A, Poluzzi E, et al. Adverse events to food supplements containing red yeast rice: comparative analysis of FAERS and CAERS reporting systems. Drug Saf 2018;41(8):745-52. doi: 10.1007/s40264-018-0661-3. PubMed
Mercurio V, Pucci G, Bosso G, et al. A nutraceutical combination reduces left ventricular mass in subjects with metabolic syndrome and left ventricular hypertrophy: A multicenter, randomized, double-blind, placebo-controlled trial. Clin Nutr. 2020;39(5):1 PubMed
Prescribing Information. Mevacor (lovastatin). Whitehouse Station, NJ: Merck & Co., Inc., February 2012.
Cicero AFG, Kennedy C, Knezevic T, et al. Efficacy and Safety of Armolipid Plus(®): An Updated PRISMA Compliant Systematic Review and Meta-Analysis of Randomized Controlled Clinical Trials. Nutrients 2021;13(2):638. PubMed
Cicero AFG, Bove M, Cincione RI, Fogacci F, Veronesi M. Effect of combined lipid-lowering and antioxidant nutraceutical on plasma lipids, endothelial function, and estimated cardiovascular disease risk in moderately hypercholesterolemic patients: a double
7-20-21 FDA Drug Safety Communication. FDA requests removal of strongest warning against using cholesterol-lowering statins during pregnancy; still advises most pregnant patients should stop taking statins. Available at: https://www.fda.gov/drugs/drug-s
García-García MD, Bellido Muñoz F, Cordero Ruiz P, Caunedo Álvarez Á. Drug-induced liver injury associated to red yeast rice. Rev Esp Enferm Dig 2023. PubMed
Santos S, Gomes S, Carvalho I, Bonito I, Carmo C. Rhabdomyolysis Related to Red Yeast Rice Ingestion. Cureus 2023;15(1):e33532. PubMed
Banach M, Norata GD. Rhabdomyolysis or severe acute hepatitis associated with the use of red yeast rice extracts: an update from the adverse event reporting systems. Curr Atheroscler Rep 2023;25(11):879-888. PubMed
Wang YH, Zhang SS, Li HT, Zhi HW, Wu HY. Rhabdomyolysis-induced acute kidney injury after administration of a red yeast rice supplement: A case report. World J Clin Cases 2023;11(23):5547-5553. PubMed
Norata GD, Banach M. The Impact of Red Yeast Rice Extract Use on the Occurrence of Muscle Symptoms and Liver Dysfunction: An Update from the Adverse Event Reporting Systems and Available Meta-Analyses. Nutrients 2024;16(3):444. PubMed
Trogkanis E, Karalexi MA, Sergentanis TN, Kornarou E, Vassilakou T. Safety and Efficacy of the Consumption of the Nutraceutical "Red Yeast Rice Extract" for the Reduction of Hypercholesterolemia in Humans: A Systematic Review and Meta-Analysis. Nutrients PubMed
Maiguma M, Kihara M, Hamaguchi M, et al. Successful treatment of acute tubulointerstitial nephritis probably due to Benikoji CholesteHelp(®), a supplement containing red yeast rice. CEN Case Rep 2024. PubMed
Oda K, Murata T, Tanaka F, et al. A case of acute kidney injury and Fanconi syndrome while taking multiple supplements, including Red Yeast Rice Cholesterol Help(®). CEN Case Rep 2024. PubMed
Miyazaki R, Takahashi Y, Kawamura T, Ueda H, Tsuboi N, Yokoo T. Acute kidney tubular injury after ingestion of red yeast rice supplement. Clin Kidney J 2024;17(6):sfae151. PubMed

Medication overviews come from MedlinePlus (NIH); supplement label data from the NIH Dietary Supplement Label Database. Content is written and reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.

Pharmacist Counseling Corner

Taking Red Yeast Rice and Acyclovir Together: Common Questions

Is it safe to take Red Yeast Rice with Acyclovir?

We do not list a known interaction between Red Yeast Rice and Acyclovir. That does not guarantee the combination is risk-free, so confirm with your pharmacist or doctor — especially if you take other medications or have a health condition.

Do Red Yeast Rice and Acyclovir have any of the same side effects?

Yes — our sources link each of them separately to 7 of the same effects. That is not an interaction: neither changes how your body handles the other. It does mean that if one of those effects turns up, it can be harder to tell which one is behind it. They are listed on this page with the source behind each.

How was the Red Yeast Rice and Acyclovir combination checked?

Interactions in our licensed database are recorded against drug classes. Acyclovir is filed under 6 classifications, and Red Yeast Rice has documented interactions with 6 drug classes — none of Acyclovir's classifications are among them. A medication can belong to classes beyond those recorded in our dataset, so this describes how the check was run rather than guaranteeing safety.

Does Red Yeast Rice interact with any other medications?

Yes. Red Yeast Rice has 477 documented drug interactions in our database — Acyclovir is simply not one of them. If you take anything else, it is worth checking each one; they are all listed on this page.

Does Acyclovir interact with any supplements?

Yes. Acyclovir has documented interactions with 37 supplements in our database — Red Yeast Rice is not one of them. The Acyclovir interaction page linked on this page lists every one, ranked by severity.

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

Where next

Keep Exploring

Red Yeast Rice monograph Uses, safety profile, and every drug interaction in one place Acyclovir drug information The full plain-English guide to this medication Acyclovir supplement interactions Every supplement checked against Acyclovir, ranked by severity Supplement interaction checker Check any supplement or product against your medications Browse medications A–Z Every drug we’ve checked against herbs & supplements References The 50 citations behind this page Ask a pharmacist Free, personal answer from our licensed team

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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.