Drug & supplement interaction

Kava + Ranitidine Bismuth Citrate

Ranitidine Bismuth Citrate brand name: Tritec.

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

Kava has a moderate interaction with Ranitidine Bismuth Citrate. It is unclear if kava inhibits P-glycoprotein (P-gp); research is conflicting.

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

Kava and Ranitidine Bismuth Citrate

Here is the interaction we found between these two, with the evidence behind it.

Moderate

P-GLYCOPROTEIN SUBSTRATES

Why this applies to Ranitidine Bismuth Citrate

Ranitidine Bismuth Citrate falls under P-GLYCOPROTEIN SUBSTRATES — the group Kava interacts with.

It is unclear if kava inhibits P-glycoprotein (P-gp); research is conflicting.
In vitro research shows that kava can inhibit P-gp efflux. However, a clinical study in healthy volunteers shows that taking kava standardized to provide 225 mg kavalactones daily for 14 days does not affect the pharmacokinetics of digoxin, a P-gp substrate. It is possible that the use of other P-gp substrates or higher doses of kava might still inhibit P-gp.
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 your heartburn medicine. Ranitidine is moved around the body partly by a transporter called P-glycoprotein. In lab dish studies, kava appeared to slow this transporter down, which in theory could let a bit more ranitidine stay in your system. If that happened, you might notice slightly stronger effects or mild side effects like headache, dizziness, or constipation (the bismuth part can also darken your stool and tongue, which is harmless).

But here's the reassuring part: this concern comes only from test-tube research, and a human study using a similar P-gp drug (digoxin) showed kava made no real difference. So this is mostly theoretical. Still, since kava can be hard on the liver, it's worth a quick chat with your pharmacist before combining them.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Weiss J, Sauer A, Frank A, Unger M. Extracts and kavalactones of Piper methysticum G. Forst (kava-kava) inhibit P-glycoprotein in vitro. Drug Metab Dispos 2005;33:1580-3. PubMed
  2. Gurley BJ, Swain A, Barone GW, et al. Effect of goldenseal (Hydrastis canadensis) and kava kava (Piper methysticum) supplementation on digoxin pharmacokinetics in humans. Drug Metab Dispos 2007;35:240-5. PubMed
  3. Asher GN, Corbett AH, Hawke RL. Common Herbal Dietary Supplement-Drug Interactions. Am Fam Physician. 2017;96(2):101-107.

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

Kava Also Interacts With Other Medications

Kava has 248 major, 580 moderate, 338 minor known drug interactions in our database — the Ranitidine Bismuth Citrate one above is one of them. If you take anything else, check it against the full list below.

Major 248 Moderate 580 Minor 338 No known interaction 1,664 (incl. Ranitidine Bismuth Citrate)
Taking anything else?

Check Another of Your Medications Against Kava

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

From our Q&A

Questions About Kava or Ranitidine Bismuth Citrate

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

This page covers Kava only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Ranitidine Bismuth Citrate page lists 73 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), St. John's Wort (major), African Wild Potato (moderate), Banderol (moderate) and Beer (moderate).

By severity: 2 major · 43 moderate · 28 minor.

Open the Ranitidine Bismuth Citrate interaction page

One more smart check

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

We hold 403 real supplement products containing Kava, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Kava. Your product may carry other ingredients that interact with Ranitidine Bismuth Citrate too, on top of Kava — 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 Kava and Ranitidine Bismuth Citrate 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 Kava
Top 25%

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

29 days ago today
Medication Ranitidine Bismuth Citrate
Steady interest

#2,617 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 Kava

What is Kava?

Kava
  • Anxiety and stress
  • Restlessness
  • Trouble sleeping
  • Relaxation in social or cultural settings
  • Menopausal symptoms

Kava is a Pacific Island plant traditionally used to promote relaxation and ease anxiety, and some studies suggest it may help mild anxiety. However, kava has been linked to rare but serious liver damage, so it should be used with caution, avoided by people with liver problems, and only used after talking with your pharmacist or doctor.

Read the full Kava monograph & all interactions
Medication

About Ranitidine

What Is Ranitidine Used For?

Brand name: Tritec

Ranitidine treats a range of stomach acid–related conditions. Prescription-strength ranitidine (capsules, tablets, and oral solution) is used for active duodenal ulcers (ulcers in the small intestine), active benign gastric ulcers (stomach ulcers), GERD (acid reflux disease), erosive esophagitis (acid damage to the esophagus), and pathological hypersecretory conditions — rare disorders where the stomach makes far too much acid, such as Zollinger-Ellison syndrome. It is also used as maintenance therapy to keep duodenal and gastric ulcers from coming back after they have healed.

Over-the-counter products — including Acid Reducer and Acid Reducer 150 tablets — are approved to relieve heartburn associated with acid indigestion and sour stomach, and to prevent that heartburn when taken before eating or drinking foods that trigger it.

See full Ranitidine drug information Ranitidine NDC codes and packages
Keep checking

Other Drugs & Kava

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

248Major
580Moderate
338Minor
1,663No known interaction
248 Major 580 Moderate 338 Minor 1,663 No interaction
Major

248 interactions

Showing 60 of 248 major interactions — see all 248 on the Kava page.

Moderate

580 interactions

Showing 60 of 580 moderate interactions — see all 580 on the Kava page.

Minor

338 interactions

Showing 60 of 338 minor interactions — see all 338 on the Kava page.

No interaction 1,663 drugs checked — show the list

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

Showing the 60 most looked-up of 1,663 medications checked with no known interaction — see the full Kava list.

See the full Kava interactions page
See every supplement checked against Ranitidine Bismuth Citrate, 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
Kava monograph › Uses, safety, and every drug interaction in one place Ranitidine Bismuth Citrate supplement interactions › Every supplement checked against Ranitidine Bismuth Citrate, ranked by severity Ranitidine drug information › The full plain-English guide to this medication Ranitidine 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 Kava and Ranitidine Bismuth Citrate Together: Common Questions

Can you take Kava with Ranitidine Bismuth Citrate?
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.
How serious is the Kava and Ranitidine Bismuth Citrate 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 Ranitidine Bismuth Citrate and Kava?

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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.