Drug & supplement interaction

Turmeric + Verapamil

Verapamil brand names: Isoptin SR, Verelan, Isoptin, Calan SR, Verelan SR, and others.

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

Verapamil falls into 4 drug categories that Turmeric can interact with; the most serious is rated moderate. Theoretically, turmeric might increase the risk of liver damage when taken with hepatotoxic drugs.

Read the full interaction report
SeverityModerate
LikelihoodPossible
Interactions4
EvidenceD
What do Severity, Likelihood & Evidence mean?
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Interaction report

Turmeric and Verapamil

These two interact in 4 distinct ways. Each one is explained separately below.

Why Are There 4 Interactions?

Turmeric interacts with whole categories of medication. Verapamil falls into 4 of those categories, so it can interact with Turmeric in 4 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 4

Why this applies to Verapamil

Verapamil falls under HEPATOTOXIC DRUGS — the group Turmeric interacts with.

Theoretically, turmeric might increase the risk of liver damage when taken with hepatotoxic drugs.
There is concern that turmeric might cause hepatotoxicity, especially when highly bioavailable formulations are used in high doses.
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 for turmeric and verapamil: this isn't about turmeric changing how verapamil works in your blood. Instead, the concern is that both can put a little extra stress on your liver. There have been a handful of reports tying concentrated turmeric (curcumin) products to liver irritation, especially the highly absorbable, high-dose formulas. Stack that on top of a medication your liver also has to process, and in theory the risk of liver trouble could add up.

I'll be honest, this is mostly theoretical and based on scattered anecdotes, not strong studies. The turmeric you sprinkle on food is very unlikely to matter. If you take a concentrated curcumin supplement, it's worth mentioning to your pharmacist or doctor, who can keep an eye on your liver if needed. Watch for things like yellowing skin or eyes, dark urine, or unusual tiredness, and call your provider if those show up.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Lombardi N, Crescioli G, Maggini V, et al. Acute liver injury following turmeric use in Tuscany: an analysis of the Italian Phytovigilance database and systematic review of case reports. Br J Clin Pharmacol. 2020. PubMed
  2. Sohal A, Alhankawi D, Sandhu S, Chintanaboina J. Turmeric-induced hepatotoxicity: Report of 2 cases. Int Med Case Rep J 2021;14:849-852. PubMed
  3. 109288 Halegoua-DeMarzio D, Navarro V, Ahmad J, et al. Liver injury associated with turmeric-A growing problem: Ten cases from the drug-induced liver injury network [DILIN]. Am J Med. 2022:S0002-9343(22)00740-9. PubMed
  4. Arzallus T, Izagirre A, Castiella A, Torrente S, Garmendia M, Zapata EM. Drug induced autoimmune hepatitis after turmeric intake. Gastroenterol Hepatol 2023. PubMed
Moderate

CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES

2 of 4

Verapamil also falls under CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES.

Turmeric might increase or decrease levels of drugs metabolized by CYP3A4.
In vitro and animal research show that turmeric and its constituents curcumin and curcuminoids inhibit CYP3A4. Also, 8 case reports from the World Health Organization (WHO) adverse drug reaction database describe increased toxicity in patients taking turmeric and cancer medications that are CYP3A4 substrates, including everolimus, ruxolitinib, ibrutinib, and palbociclib, and bortezomib. In another case report, a transplant patient presented with acute nephrotoxicity and elevated tacrolimus levels after consuming turmeric powder at a dose of 15 or more spoonfuls daily for ten days prior. It was thought that turmeric increased levels of tacrolimus due to CYP3A4 inhibition.
Conversely, other in vitro research suggests that turmeric induces CYP3A4 activity, leading to reduced levels of CYP3A4 substrates. An animal model suggests that induction of CYP3A4 occurs after daily curcumin use for 1 week. However, the induction of CYP3A4 by turmeric has not been reported in humans.
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 deal with these two. Your body clears verapamil using a liver enzyme called CYP3A4, and turmeric (mainly its curcumin) seems to nudge that enzyme in lab and animal studies. Most of that research points to turmeric slowing the enzyme, which could let verapamil build up a bit. If that happens, you might notice more of verapamil's usual effects: lower blood pressure, dizziness, a slower heartbeat, tiredness, or constipation. A few studies hint at the opposite (faster clearance, weaker effect), so the direction isn't fully settled.

The good news is the evidence is weak, mostly test tube and animal work, and the spice amounts you'd use in cooking are very unlikely to matter. Concentrated curcumin capsules are the bigger question mark. Before adding a turmeric supplement, just run it by your pharmacist or doctor.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Appiah-Opong, R., Commandeur, J. N., Vugt-Lussenburg, B., and Vermeulen, N. P. Inhibition of human recombinant cytochrome P450s by curcumin and curcumin decomposition products. Toxicology 6-3-2007;235(1-2):83-91. PubMed
  2. Hou, X. L., Takahashi, K., Kinoshita, N., Qiu, F., Tanaka, K., Komatsu, K., Takahashi, K., and Azuma, J. Possible inhibitory mechanism of Curcuma drugs on CYP3A4 in 1alpha,25 dihydroxyvitamin D3 treated Caco-2 cells. Int.J Pharm 6-7-2007;337(1-2):169-177.
  3. Valentine, S. P., Le Nedelec, M. J., Menzies, A. R., Scandlyn, M. J., Goodin, M. G., and Rosengren, R. J. Curcumin modulates drug metabolizing enzymes in the female Swiss Webster mouse. Life Sci. 4-11-2006;78(20):2391-2398. PubMed
  4. Nayeri A, Wu S, Adams E, et al. Acute Calcineurin Inhibitor Nephrotoxicity Secondary to Turmeric Intake: A Case Report. Transplant Proc. 2017;49(1):198-200. PubMed
  5. Haron MH, Dale O, Martin K, et al. Evaluation of the Herb-Drug Interaction Potential of Commonly Used Botanicals on the US Market with Regard to PXR- and AhR-Mediated Influences on CYP3A4 and CYP1A2. J Diet Suppl 2022. PubMed
  6. Pochet S, Lechon AS, Lescrainier C, et al. Herb-anticancer drug interactions in real life based on VigiBase, the WHO global database. Sci Rep 2022;12(1):14178. PubMed
  7. Dibaei M, Hosseini A, Lavasani H, Kiani-Dehkordi B, Rouini M. Assessment of metabolic interaction between curcumin and tramadol using the isolated perfused rat liver. Heliyon 2024;10(15):e35070. PubMed
Minor

CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES

3 of 4

Verapamil also falls under CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES.

Theoretically, turmeric might increase levels of drugs metabolized by CYP1A2. However, research is conflicting.
In vitro and animal research show that the turmeric constituent, curcumin, inhibits CYP1A2. However, other in vitro research suggests that curcumin does not significantly affect CYP1A2.
Severity Minor 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 for you. The thinking is that curcumin (the active part of turmeric) might slow down a liver enzyme called CYP1A2, which can play a role in clearing some medicines. If your verapamil were broken down mainly by that enzyme, slowing it could let a bit more drug build up, possibly nudging effects like lower blood pressure, a slower heart rate, dizziness, or constipation.

That said, I want to be honest about how weak this is. It comes only from lab and animal studies, the results even disagree with each other, and verapamil is mostly handled by a different enzyme (CYP3A4), not CYP1A2. So normal cooking amounts of turmeric are very unlikely to matter. If you're considering concentrated curcumin capsules, just run it by your pharmacist or doctor first.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Thapliyal R, Deshpande SS, Maru GB. Mechanism(s) of turmeric-mediated protective effects against benzo(a)pyrene-derived DNA adducts. Cancer Lett 2002;175:79-88. PubMed
  2. Appiah-Opong, R., Commandeur, J. N., Vugt-Lussenburg, B., and Vermeulen, N. P. Inhibition of human recombinant cytochrome P450s by curcumin and curcumin decomposition products. Toxicology 6-3-2007;235(1-2):83-91. PubMed
  3. Price, R. J., Scott, M. P., Giddings, A. M., Walters, D. G., Stierum, R. H., Meredith, C., and Lake, B. G. Effect of butylated hydroxytoluene, curcumin, propyl gallate and thiabendazole on cytochrome P450 forms in cultured human hepatocytes. Xenobiotica 2 PubMed
  4. Oetari, S., Sudibyo, M., Commandeur, J. N., Samhoedi, R., and Vermeulen, N. P. Effects of curcumin on cytochrome P450 and glutathione S-transferase activities in rat liver. Biochem Pharmacol 1-12-1996;51(1):39-45. PubMed
Minor

P-GLYCOPROTEIN SUBSTRATES

4 of 4

Verapamil also falls under P-GLYCOPROTEIN SUBSTRATES.

Theoretically, turmeric might increase the absorption of P-glycoprotein substrates.
In vitro and animal research shows that curcuminoids and other constituents found in turmeric can inhibit P-glycoprotein expression and activity.
Severity Minor 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 for verapamil: your body uses a little cellular pump called P-glycoprotein to push some of the drug back out of your gut and limit how much gets absorbed. Lab and animal studies hint that the curcumin in turmeric can slow that pump down. In theory, that could let a bit more verapamil into your bloodstream than usual.

If that happened, you might notice more of verapamil's typical effects, like lower blood pressure, dizziness, a slower heartbeat, or constipation. That said, this is very early evidence (test tubes and animals, not people), and the cooking amount of turmeric in your food is unlikely to do much. Concentrated curcumin capsules are a different story, so it's worth a quick chat with your pharmacist or doctor before starting one.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Junyaprasert, V. B., Soonthornchareonnon, N., Thongpraditchote, S., Murakami, T., and Takano, M. Inhibitory effect of Thai plant extracts on P-glycoprotein mediated efflux. Phytother.Res 2006;20(1):79-81. PubMed
  2. Ampasavate, C., Sotanaphun, U., Phattanawasin, P., and Piyapolrungroj, N. Effects of Curcuma spp. on P-glycoprotein function. Phytomedicine. 2010;17(7):506-512. PubMed
  3. Hou, X. L., Takahashi, K., Tanaka, K., Tougou, K., Qiu, F., Komatsu, K., Takahashi, K., and Azuma, J. Curcuma drugs and curcumin regulate the expression and function of P-gp in Caco-2 cells in completely opposite ways. Int.J Pharm 6-24-2008;358(1-2):224-2 PubMed
  4. Choi, B. H., Kim, C. G., Lim, Y., Shin, S. Y., and Lee, Y. H. Curcumin down-regulates the multidrug-resistance mdr1b gene by inhibiting the PI3K/Akt/NF kappa B pathway. Cancer Lett. 1-18-2008;259(1):111-118.
  5. Zhang, W., Tan, T. M., and Lim, L. Y. Impact of curcumin-induced changes in P-glycoprotein and CYP3A expression on the pharmacokinetics of peroral celiprolol and midazolam in rats. Drug Metab Dispos. 2007;35(1):110-115. PubMed
  6. Limtrakul, P., Chearwae, W., Shukla, S., Phisalphong, C., and Ambudkar, S. V. Modulation of function of three ABC drug transporters, P-glycoprotein (ABCB1), mitoxantrone resistance protein (ABCG2) and multidrug resistance protein 1 (ABCC1) by tetrahydrocu
  7. Holland, M. L., Panetta, J. A., Hoskins, J. M., Bebawy, M., Roufogalis, B. D., Allen, J. D., and Arnold, J. C. The effects of cannabinoids on P-glycoprotein transport and expression in multidrug resistant cells. Biochem.Pharmacol 4-14-2006;71(8):1146-1154 PubMed
  8. Tang, X. Q., Bi, H., Feng, J. Q., and Cao, J. G. Effect of curcumin on multidrug resistance in resistant human gastric carcinoma cell line SGC7901/VCR. Acta Pharmacol Sin. 2005;26(8):1009-1016. PubMed
  9. Nabekura, T., Kamiyama, S., and Kitagawa, S. Effects of dietary chemopreventive phytochemicals on P-glycoprotein function. Biochem.Biophys.Res Commun. 2-18-2005;327(3):866-870. PubMed
  10. Romiti, N., Tongiani, R., Cervelli, F., and Chieli, E. Effects of curcumin on P-glycoprotein in primary cultures of rat hepatocytes. Life Sci. 1998;62(25):2349-2358. PubMed
  11. Yue, G. G., Cheng, S. W., Yu, H., Xu, Z. S., Lee, J. K., Hon, P. M., Lee, M. Y., Kennelly, E. J., Deng, G., Yeung, S. K., Cassileth, B. R., Fung, K. P., Leung, P. C., and Lau, C. B. The role of turmerones on curcumin transportation and P-glycoprotein acti
  12. Pochet S, Lechon AS, Lescrainier C, et al. Herb-anticancer drug interactions in real life based on VigiBase, the WHO global database. Sci Rep 2022;12(1):14178. 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

Turmeric Also Interacts With Other Medications

Turmeric has 1,055 moderate, 77 minor known drug interactions in our database — the Verapamil one above is among them. If you take anything else, check it against the full list below.

Moderate 1,055 Minor 77 No known interaction 1,698 (incl. Verapamil)
Taking anything else?

Check Another of Your Medications Against Turmeric

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

From our Q&A

Questions About Turmeric or Verapamil

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Turmeric or Verapamil, 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 Verapamil

This page covers Turmeric only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Verapamil page lists 295 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), American Hellebore (major), American Mistletoe (major), Beer (major) and Coleus (major).

By severity: 10 major · 245 moderate · 40 minor.

From our pharmacist’s overview on the Verapamil page

“This is one of the longer interaction lists we publish, and with verapamil (Calan, Verelan) it warrants genuine care, starting with the ten major-rated entries. Verapamil lowers blood pressure and slows the heart, so most of the 295 ingredients on file either push that effect further than intended or change how much of the drug reaches…”

Reviewed by 2 · Jul 18, 2026

Open the Verapamil interaction page

One more smart check

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

We hold 1,368 real supplement products containing Turmeric, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Turmeric. Your product may carry other ingredients that interact with Verapamil too, on top of Turmeric — 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 Turmeric and Verapamil 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 Turmeric
Top 5%

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

29 days ago today
Medication Verapamil
Top 25%

#705 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 Turmeric

What is Turmeric?

Turmeric
  • Joint pain and arthritis
  • Inflammation
  • Digestive upset
  • Antioxidant support
  • Skin conditions

Turmeric is a popular spice whose main active compounds, curcuminoids, are studied mostly for inflammation and joint pain. Some research is promising, but quality is mixed and curcumin is poorly absorbed on its own. For most people, dietary amounts are safe, but talk to your pharmacist or doctor before taking concentrated supplements, especially if you are pregnant, nursing, or have a medical condition.

Read the full Turmeric monograph & all interactions
Medication

About Verapamil

What Is Verapamil Used For?

Brand names: Isoptin SR, Verelan, Isoptin, Calan SR, Verelan SR, Calan, Covera HS, Verap, Veramil

Verapamil tablets and film-coated tablets are used to treat angina — including vasospastic (Prinzmetal's) angina, unstable angina, and chronic stable angina — as well as certain abnormal heart rhythms (arrhythmias) and high blood pressure (essential hypertension). For arrhythmias, regular-release tablets are used alongside digoxin to control heart rate in atrial flutter or atrial fibrillation, and to help prevent episodes of paroxysmal supraventricular tachycardia (SVT), a type of rapid heartbeat.

Extended-release and sustained-release oral forms (tablets and capsules) are indicated specifically for high blood pressure. Verapamil hydrochloride injection is used in hospital settings for rapid conversion of SVT to normal rhythm and for temporary control of fast heart rates in atrial flutter or atrial fibrillation.

See full Verapamil drug information
Keep checking

Other Drugs & Turmeric

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

0Major
1,055Moderate
77Minor
1,697No known interaction
1,055 Moderate 77 Minor 1,697 No interaction
Moderate

1,055 interactions

Showing 60 of 1,055 moderate interactions — see all 1,055 on the Turmeric page.

Minor

77 interactions

Showing 60 of 77 minor interactions — see all 77 on the Turmeric page.

No interaction 1,697 drugs checked — show the list

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

Showing the 60 most looked-up of 1,697 medications checked with no known interaction — see the full Turmeric list.

See the full Turmeric interactions page
See every supplement checked against Verapamil, 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
Turmeric monograph › Uses, safety, and every drug interaction in one place Verapamil supplement interactions › Every supplement checked against Verapamil, ranked by severity Verapamil 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 Turmeric and Verapamil Together: Common Questions

Can you take Turmeric with Verapamil?
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 4 interactions listed for Turmeric and Verapamil?
Verapamil belongs to more than one drug category, and Turmeric 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 Turmeric and Verapamil 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 Verapamil and Turmeric?

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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.