Drug & supplement interaction

Devil's Claw + Tolvaptan

Tolvaptan brand names: Samsca, Jynarque.

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

Tolvaptan falls into 2 drug categories that Devil's Claw can interact with; the most serious is rated moderate. Theoretically, devil's claw might increase levels of drugs metabolized by CYP3A4.

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

Devil's Claw and Tolvaptan

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. Tolvaptan 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 (Moderate).

Moderate

CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES

1 of 2

Why this applies to Tolvaptan

Tolvaptan falls under CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES — the group Devil's Claw interacts with.

Theoretically, devil's claw might increase levels of drugs metabolized by CYP3A4.
In vitro research shows that devil's claw might inhibit CYP3A4, although this 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 gist with tolvaptan (Samsca or Jynarque). Your body clears this medication using a liver enzyme called CYP3A4. Lab studies hint that devil's claw might slow that enzyme down a bit. If that happened in a real person, tolvaptan could build up higher than expected, which means stronger water loss: more urination, thirst, dry mouth, and possibly dizziness or rising sodium levels.

The important part is that this is only a test-tube finding, not something seen in actual patients, so I wouldn't lose sleep over it. Still, tolvaptan is a drug that needs careful monitoring, so before adding devil's claw, check in with your pharmacist or kidney doctor so they can keep an eye on your labs and how you feel.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Unger M, Frank A. Simultaneous determination of the inhibitory potency of herbal extracts on the activity of six major cytochrome P450 enzymes using liquid chromatography/mass spectrometry and automated online extraction. Rapid Commun Mass Spectrom 2004;1 PubMed
Minor

P-GLYCOPROTEIN SUBSTRATES

2 of 2

Tolvaptan also falls under P-GLYCOPROTEIN SUBSTRATES.

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 gist for tolvaptan (Samsca or Jynarque). Your body uses a little cellular pump called P-glycoprotein to move many drugs out of cells. Lab studies hint that devil's claw may slow this pump down. Since tolvaptan is one of the medicines that pump helps handle, blocking it could nudge tolvaptan levels up a bit, which in theory might mean stronger effects like more frequent urination, increased thirst, dry mouth, or feeling lightheaded.

I want to be honest, though: this is based only on test-tube research, not real people, so we truly don't know if it matters in everyday life. The interaction is rated minor. Since tolvaptan is closely monitored for liver and sodium effects, just give your pharmacist or doctor a heads-up before adding devil's claw.

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

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 732 moderate, 72 minor known drug interactions in our database — the Tolvaptan one above is among them. If you take anything else, check it against the full list below.

Moderate 732 Minor 72 No known interaction 2,026 (incl. Tolvaptan)
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.

Everything else you take

See Every Supplement That Interacts With Tolvaptan

This page covers Devil's Claw only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Tolvaptan page lists 145 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Grapefruit (major), St. John's Wort (major), Acacia Rigidula (moderate) and Adrafinil (moderate).

By severity: 3 major · 104 moderate · 38 minor.

From our pharmacist’s overview on the Tolvaptan page

“People taking tolvaptan (Samsca, Jynarque) for polycystic kidney disease or low blood sodium are on a drug whose blood level depends heavily on one liver enzyme, CYP3A4, and that is exactly where most of these 145 supplements interfere. Grapefruit can drive tolvaptan levels up, St.”

Reviewed by 2 · Jul 18, 2026

Open the Tolvaptan 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 Tolvaptan 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 Tolvaptan 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%

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

29 days ago today
Medication Tolvaptan
Steady interest

#1,997 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 Tolvaptan (kidney disease)

What Is Tolvaptan (kidney disease) Used For?

Brand names: Samsca, Jynarque

Tolvaptan (brand name Jynarque) is used to slow the decline of kidney function in adults who have autosomal dominant polycystic kidney disease (ADPKD) — a genetic condition where fluid-filled cysts grow in the kidneys over time, gradually damaging them. It is specifically for people whose disease is at risk of progressing quickly.

It does not cure ADPKD, but it works to slow down how fast the kidneys deteriorate, helping preserve kidney function for longer.

See full Tolvaptan (kidney disease) drug information Tolvaptan NDC codes and packages
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
732Moderate
72Minor
2,025No known interaction
732 Moderate 72 Minor 2,025 No interaction
Moderate

732 interactions

Showing 60 of 732 moderate interactions — see all 732 on the Devil's Claw page.

Minor

72 interactions

Showing 60 of 72 minor interactions — see all 72 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 Tolvaptan, 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 Tolvaptan supplement interactions › Every supplement checked against Tolvaptan, ranked by severity Tolvaptan (kidney disease) drug information › The full plain-English guide to this medication Tolvaptan NDC codes and packages › Every package, labeler and price in the FDA directory 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 Tolvaptan Together: Common Questions

Can you take Devil's Claw with Tolvaptan?
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 2 interactions listed for Devil's Claw and Tolvaptan?
Tolvaptan 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 Tolvaptan 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 Tolvaptan 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.