Drug & supplement interaction

Devil's Claw + Cimetidine

Cimetidine brand names: Tagamet HB, Tagamet, Cimetidine Injection.

Minor Interaction
Medically reviewed by · Updated October 2026
The bottom line Minor

Cimetidine falls into 2 drug categories that Devil's Claw can interact with; the most serious is rated minor. Theoretically, devil's claw might increase levels of P-glycoprotein substrates.

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

Devil's Claw and Cimetidine

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

Why Are There 2 Interactions?

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

Minor

P-GLYCOPROTEIN SUBSTRATES

1 of 2

Why this applies to Cimetidine

Cimetidine falls under P-GLYCOPROTEIN SUBSTRATES — the group Devil's Claw interacts with.

Theoretically, devil's claw might increase levels of P-glycoprotein substrates.
In vitro research shows that devil's claw inhibits P-glycoprotein, which transports many drugs out of cells. This might increase intracellular levels of P-glycoprotein substrates, although it is unclear if this effect would be clinically important.
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 short version: your body uses a kind of cellular bouncer called P-glycoprotein to push certain drugs back out of cells. Lab studies hint that Devil's Claw may slow that bouncer down. Since cimetidine is moved around by P-glycoprotein, the theory is that a little more could stay inside cells, nudging its levels up slightly.

If that happened, you might notice a touch more of cimetidine's usual mild effects, like headache, drowsiness, or loose stools. But honestly, this is only seen in test-tube research, not in people, so it's far from a sure thing. Cimetidine is also a pretty gentle, forgiving medicine. Still, it's worth a quick chat with your pharmacist before pairing the two.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Romiti N, Tramonti G, Corti A, Chieli E. Effects of Devil's Claw (Harpagophytum procumbens) on the multidrug transporter ABCB1/P-glycoprotein. Phytomedicine 2009;16:1095-100. PubMed
Minor

H2-BLOCKERS

2 of 2

Cimetidine also falls under H2-BLOCKERS.

Theoretically, devil's claw might decrease the effectiveness of H2-blockers.
Devil's claw has been reported to increase stomach acid, which might interfere with the effects of H2-blockers.
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 simple version: Cimetidine (Tagamet) works by turning down how much acid your stomach makes, which calms heartburn and helps ulcers heal. Devil's claw is sometimes reported to do the opposite, nudging your stomach to make a bit more acid. So in theory, taking the two together could blunt how well your cimetidine controls your symptoms, meaning you might notice more heartburn, indigestion, or that sour, burning feeling creeping back.

I want to be honest about the evidence here, though. This concern is mostly theoretical and based on anecdotal reports, not solid studies, so it's rated a minor interaction. If you'd like to try devil's claw for joint or back pain, just check with your pharmacist or doctor first, and keep an eye on whether your stomach symptoms change.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.

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

Devil's Claw Also Interacts With Other Medications

Devil's Claw has 733 moderate, 71 minor known drug interactions in our database — the Cimetidine one above is among them. If you take anything else, check it against the full list below.

Moderate 733 Minor 71 No known interaction 2,026 (incl. Cimetidine)
Taking anything else?

Check Another of Your Medications Against Devil's Claw

Covers the 2,830 medications we’ve checked against Devil's Claw. Pick one to open its full report.

From our Q&A

Questions About Devil's Claw or Cimetidine

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Devil's Claw or Cimetidine, 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 Cimetidine

This page covers Devil's Claw only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Cimetidine page lists 95 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Pu-erh Tea (major), St. John's Wort (major), Adrafinil (moderate) and African Wild Potato (moderate).

By severity: 3 major · 63 moderate · 29 minor.

Open the Cimetidine interaction page

One more smart check

Taking Devil's Claw as Part of a Dietary Supplement Product? Check It for Interactions

We hold 585 real supplement products containing Devil's Claw, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Devil's Claw. Your product may carry other ingredients that interact with Cimetidine too, on top of Devil's Claw — 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 Devil's Claw and Cimetidine 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 Devil's Claw
Top 25%

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

29 days ago today
Medication Cimetidine
Steady interest

#2,055 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 Devil's Claw

What is Devil's Claw?

Devil's Claw
  • Osteoarthritis pain
  • Lower back pain
  • Joint pain and stiffness
  • General inflammation
  • Digestive upset and loss of appetite

Devil's claw is a southern African plant used mainly for arthritis and back pain, and some studies suggest it may help ease these types of discomfort. The evidence is moderate at best, and product strength varies, so talk with your pharmacist or doctor before trying it, especially if you have a health condition or take medications.

Read the full Devil's Claw monograph & all interactions
Medication

About Cimetidine

What Is Cimetidine Used For?

Brand names: Tagamet HB, Tagamet, Cimetidine Injection

Cimetidine lowers stomach acid. The over-the-counter tablets (sold as Acid Controller, Acid Reducer, Basic Care Acid Reducer, Equate Cimetidine, Tagamet and others) relieve and prevent heartburn linked to acid indigestion and sour stomach.

The prescription cimetidine tablets and cimetidine hydrochloride oral solution treat stomach and digestive tract conditions. These include active duodenal ulcer, benign gastric ulcer, erosive gastroesophageal reflux disease (GERD) and pathological hypersecretory conditions. They are also used to keep duodenal ulcers from coming back after healing.

See full Cimetidine drug information
Keep checking

Other Drugs & Devil's Claw

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

0Major
733Moderate
71Minor
2,025No known interaction
733 Moderate 71 Minor 2,025 No interaction
Moderate

733 interactions

Showing 60 of 733 moderate interactions — see all 733 on the Devil's Claw page.

Minor

71 interactions

Showing 60 of 71 minor interactions — see all 71 on the Devil's Claw page.

No interaction 2,025 drugs checked — show the list

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

Showing the 60 most looked-up of 2,025 medications checked with no known interaction — see the full Devil's Claw list.

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

Can you take Devil's Claw with Cimetidine?
There is only a minor interaction, which is usually not serious. Read the full details on this page and confirm with your pharmacist before combining them.
Why are there 2 interactions listed for Devil's Claw and Cimetidine?
Cimetidine belongs to more than one drug category, and Devil's Claw 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 Devil's Claw and Cimetidine interaction?
We rate it Minor. This interaction is generally not clinically significant, but it remains worth noting and discussing with your pharmacist.

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

Still Have a Question About Cimetidine and Devil's Claw?

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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.