Drug & supplement interaction

Kava + Itraconazole

Itraconazole brand names: Sporanox, Sporanox Injection, Tolsura.

Moderate Interaction
The bottom line Moderate

Itraconazole falls into 3 drug categories that Kava can interact with; the most serious is rated moderate. Theoretically, using kava with hepatotoxic drugs might increase the risk of liver damage.

Read the full interaction report
SeverityModerate
LikelihoodPossible
Interactions3
EvidenceD
What do Severity, Likelihood & Evidence mean?
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Interaction report

Kava and Itraconazole

These two interact in 3 distinct ways. Each one is explained separately below.

Why Are There 3 Interactions?

Kava interacts with whole categories of medication. Itraconazole falls into 3 of those categories, so it can interact with Kava in 3 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 3

Why this applies to Itraconazole

Itraconazole falls under HEPATOTOXIC DRUGS — the group Kava interacts with.

Theoretically, using kava with hepatotoxic drugs might increase the risk of liver damage.
Kava has been linked with over 100 cases of hepatotoxicity. Most cases occur with excessive and prolonged use. There is some concern that kava can adversely affect the liver, especially when used in combination with hepatotoxic drugs.
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 concern with pairing kava and itraconazole: both can be tough on your liver. Itraconazole already carries warnings about liver injury, and kava has been tied to over 100 reported cases of liver damage, mostly with heavy or long-term use. Putting two liver-stressing substances together may stack that risk.

This isn't about kava changing how itraconazole works in your body. It's about overlapping strain on the same organ. Watch for warning signs like yellowing of the skin or eyes, dark urine, belly pain, unusual tiredness, or nausea. Honestly, the evidence here is mostly anecdotal and theoretical, so don't panic, but please check with your pharmacist or doctor before combining them, especially if you'll be on itraconazole for weeks.

References
  1. Escher M, Desmeules J, Giostra E, Mentha G. Hepatitis associated with Kava, a herbal remedy for anxiety. BMJ 2001;322:139.
  2. Russmann S, Lauterburg BH, Helbling A. Kava hepatotoxicity [letter]. Ann Intern Med 2001;135:68-9.
  3. Liver Toxicity With Kava. Pharmacist's Letter/Prescriber's Letter. January 2001.
  4. Consultation letter MLX 286: Proposals to prohibit the herbal ingredient Kava-Kava (Piper methysticum) in unlicensed medicines. Medicines Control Agency, United Kingdom, July 19, 2002.
  5. Li XZ, Ramzan I. Role of ethanol in kava hepatotoxicity. Phytother Res 2010;24:475-80. PubMed
  6. Chanwai, L. G. Kava toxicity. Emergency Medicine 2002;12:142-145.
Moderate

P-GLYCOPROTEIN SUBSTRATES

2 of 3

Itraconazole also falls under P-GLYCOPROTEIN SUBSTRATES.

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 short version on combining kava with itraconazole (Sporanox, Tolsura). Itraconazole is moved around your body partly by a transporter called P-glycoprotein, or P-gp. In a test tube, kava looked like it might slow that transporter down, which in theory could let a bit more itraconazole stay in your system and slightly raise the chance of side effects like nausea, headache, or stomach upset.

But honestly, the evidence here is weak. In actual people, a standardized kava dose did not change the levels of digoxin, another P-gp drug. So this is mostly lab-based and uncertain. The bigger real-world concern is that both kava and itraconazole can stress the liver, so pairing them isn't ideal. Please check with your pharmacist or doctor before using kava with this medicine.

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.
Minor

CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES

3 of 3

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

It is unclear if kava inhibits CYP3AA; research is conflicting.
Although in vitro research suggests that kava inhibits CYP3A4, more robust clinical evidence shows that kava has no effect on CYP3A4. In a clinical study in healthy volunteers, taking kava 1000 mg twice daily (containing a daily dose of 138 mg kavalactones) for 28 days had no effect on CYP3A4 activity.
Severity Minor Likelihood Unlikely Evidence B

Interaction has been demonstrated in animal or in lab research but has been shown not to occur in humans..

Dr. Brian Staiger, PharmD, BCPS
Dr. Brian Staiger explains PharmD, Clinical Pharmacist

Here's the gist for itraconazole (Sporanox, Tolsura) and kava. Itraconazole is cleared by a liver enzyme called CYP3A4, and there was a theory that kava might slow that enzyme down. If that were true, itraconazole could build up and cause more side effects like nausea, headache, or stomach upset. But the better-quality human research found that kava did not meaningfully change CYP3A4 activity, so this interaction is rated minor and unlikely.

What I'd watch more closely is your liver. Both kava and itraconazole have been tied to rare liver problems, so combining them adds a little extra strain. Before pairing them, please check in with your pharmacist or doctor, especially if you notice yellowing skin, dark urine, or unusual tiredness.

References
  1. Mathews JM, Etheridge AS, Black SR. Inhibition of human cytochrome P450 activities by kava extract and kavalactones. Drug Metab Dispos 2002;30:1153-7. PubMed
  2. 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
  3. Gurley BJ, Gardner SF, Hubbard MA, et al. In vivo effects of goldenseal, kava kava, black cohosh, and valerian on human cytochrome P450 1A2, 2D6, 2E1, and 3A4/5 phenotypes. Clin Pharmacol Ther 2005;77:415-26. PubMed
  4. 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, 576 moderate, 341 minor known drug interactions in our database — the Itraconazole one above is among them. If you take anything else, check it against the full list below.

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 Itraconazole

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 Itraconazole, 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 Itraconazole

This page covers Kava only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Itraconazole page lists 182 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Beer (major), Grapefruit (major), Siberian Cocklebur (major) and St. John's Wort (major).

By severity: 6 major · 136 moderate · 40 minor.

From our pharmacist’s overview on the Itraconazole page

“Serious fungal infections are what itraconazole (Sporanox, Tolsura) is for, and the drug travels through CYP3A4, the liver enzyme that also handles a large share of supplements. That overlap is why this list reaches 182 ingredients, and it earns genuine care; start with the six rated major.”

Reviewed by 2 · Jul 18, 2026

Open the Itraconazole 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 Itraconazole 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 Itraconazole 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%

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

29 days ago today
Medication Itraconazole
Top half

#855 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 Itraconazole

What Is Itraconazole Used For?

Brand names: Sporanox, Sporanox Injection, Tolsura

Itraconazole capsules (including Sporanox capsules and generic itraconazole capsules) treat serious fungal infections — blastomycosis, histoplasmosis, and aspergillosis — in both people with normal immune systems and those who are immunocompromised. Capsule forms are also approved for nail fungus (onychomycosis) caused by dermatophytes in non-immunocompromised patients. Tolsura (a gelatin-coated capsule formulation) treats blastomycosis, histoplasmosis, and aspergillosis in adults, but is not approved for nail fungus and is not interchangeable with other itraconazole products.

Itraconazole oral solution is specifically approved for oropharyngeal candidiasis (thrush — a fungal infection of the mouth) and esophageal candidiasis (a fungal infection of the food pipe). Only the oral solution has been shown to work for these mouth and throat infections; capsules cannot be substituted for this use.

See full Itraconazole drug information
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
576Moderate
341Minor
1,664No known interaction
Major

248 interactions

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

Moderate

576 interactions

Showing 60 of 576 moderate interactions — see all 576 on the Kava page.

Minor

341 interactions

Showing 60 of 341 minor interactions — see all 341 on the Kava page.

No interaction 1,664 drugs checked — show the list
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

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Pharmacist Counseling Corner

Taking Kava and Itraconazole Together: Common Questions

Can you take Kava with Itraconazole?
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 3 interactions listed for Kava and Itraconazole?
Itraconazole belongs to more than one drug category, and Kava 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 Kava and Itraconazole 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

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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.