Kava Ingredients & Drug Interactions
What is this page for?
First and foremost: checking Kava against your medications. The heart of this page is the interaction checker and the full interaction report — how this product’s ingredients may interact with prescription and over-the-counter medicines you may be taking.
Around that, we add a pharmacist’s high-level view of the product as a whole — what’s inside, the evidence for its stated use, how transparent the label is, and what safety data exists — so you can see the full picture in one place. It’s educational information from our licensed clinical databases and the clinical staff at HelloPharmacist — not medical advice — and we don’t sell or endorse products. Our editorial policy
Kava is a dietary supplement by Thymely Solutions with 1 active ingredient. Its ingredients are commonly taken for anxiety and stress, restlessness, trouble sleeping.Based on those ingredients, 1,166 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are selectively imported Vanuatu Kava. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.
Check Your Meds Against Kava by Thymely Solutions
Ask about any prescription or over-the-counter medication and we check it for interactions with Kava by Thymely Solutions — and tell you which ingredient is responsible.
AI summaries are generated from our interaction database for education only — always confirm with your pharmacist. How we use AI
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HelloPharmacist Scorecard of Kava by Thymely Solutions
Our pharmacy team’s full take, with four database checks built into the cards below — a summary of what is known, not a grade of the product itself.
What’s inside
Full disclosure
Thymely Solutions Kava contains one active ingredient: selectively imported Vanuatu kava. The product comes as a liquid with grain alcohol and deionized water as inactive ingredients.
Does it work?
Leans against
The evidence on kava's effectiveness is mixed and often insufficient. For generalized anxiety disorder, the data suggests it may be ineffective.
For insomnia and sexual arousal, we don't have enough reliable evidence to rate whether it works. For epilepsy, the same applies—the evidence is too limited to say.
If you're considering kava for anxiety, have that conversation with your doctor, since the research doesn't consistently back its use.
How safe is it?
Well-documented data
Kava is generally well tolerated when taken by mouth, but it carries real safety concerns. The most serious is liver injury—over 100 cases of hepatotoxicity have been reported worldwide, especially with heavy, long-term use; in vulnerable people, damage can show up within 3 to 4 weeks.
Common side effects include drowsiness, dry mouth, dizziness, upset stomach, headache, memory problems, and tremor. In one trial, people taking kava had a 3.2-fold higher risk of tremors compared to placebo.
Kava is not safe during pregnancy and should be avoided. While breastfeeding, it should also be avoided because of the lack of safety data and the possibility it could pass to your infant.
Meds to double-check
Major interaction found
Before taking this kava product, check with your doctor or pharmacist if you're on CNS depressants (sedatives, sleeping pills, anxiety medications, opioids)—the combination raises the risk of dangerous drowsiness. Also double-check any medications broken down by liver enzymes CYP2C19, CYP2C9, or CYP2E1, as kava can raise their levels.
Finally, ask about any drugs that interact with haloperidol or ropinirole, and any medicines that rely on P-glycoprotein transport, since kava may affect how those work.
The bottom line
Scorecard at a glanceFully disclosed formula with graded evidence leaning against its stated purpose. Major medication interactions have been identified, and safety information is well characterized.
Kava may appeal to someone looking for anxiety relief, but the liver injury risk and broad medication interactions make it a supplement you need to discuss carefully with your doctor or pharmacist first. If you take any prescription medication, CNS depressants, or drugs that go through your liver, you'll want to check your specific medications before considering kava.
This isn't something to start on your own—get personalized advice from your healthcare provider.
Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI
Assessment coverage: 1 of 1 active ingredient matched to our full ingredient reviews (monographs). Based on the product label dated Dec 22, 2019.
This Scorecard evaluates available label information, ingredient evidence, and known medication-safety considerations. It does not independently verify product identity, purity, potency, contamination, or manufacturing quality. How these ratings are computed
General information
Key facts about Kava, straight from the product label.
| Brand | Thymely Solutions |
|---|---|
| Barcode (UPC) | 788332042119 |
| Net contents | 1 fl. Oz.; 30 mL |
| Market status | On market |
| Date entered into DSLD | Dec 22, 2019 |
| DSLD ID | 211661 |
| Product type | Botanical |
| Supplement form | Liquid |
| Dietary claims / uses | All Other |
| Intended target group(s) | Adult (18 - 50 Years), Kosher, Women (not pregnant or lactating) |
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.
Supplement Facts
The label details for Kava by Thymely Solutions, sourced from the NIH Dietary Supplement Label Database.
Supplement Facts
| Ingredient | Amount | % DV |
|---|---|---|
| selectively imported Vanuatu Kava | 500 mg | -- |
Other ingredients: Grain Alcohol, deionized Water
Tap any ingredient to jump to its full detail below.
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
Suggested/Recommended/Usage/Directions
Suggested Use: 30 drops in water or juice, 1-3 times daily, or as needed.
Shake well before using.
Precautions
Warnings: Do not take during pregnancy or while nursing.
Keep out of the reach of children.
FDA Statement of Identity
Herbal Supplement
Seals/Symbols
K Parve K-1604
Formula
K Parve K-1604
Is this label outdated? Report a formula or label change and our pharmacy team will review it.
Kava by Thymely Solutions label
The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.
Label images are published by the NIH Dietary Supplement Label Database for the version of this product on file. Always read your actual product label.
View the full label (PDF)The Ingredients in Kava by Thymely Solutions
This is the 1 active ingredient this product is made of. Select it to open its full monograph.
Serving size1 mL Dosage formLiquid Servings per container30 Amounts shown are per serving.
Selectively imported Vanuatu Kava
Interacts with1,166 drugs
Kava is a Pacific Island plant traditionally used to promote relaxation and ease anxiety, and some studies suggest it may help mild anxiety. However,...
Selectively imported Vanuatu Kava monograph & interactionsOther (inactive) ingredients: Grain Alcohol, Deionized Water. These complete the product’s ingredient list but are not active constituents.
Kava by Thymely Solutions Drug Interactions
HelloPharmacist Interaction Report
Thymely Solutions Kava is a single-ingredient supplement that interacts with medications in several important ways.
The most serious concern is with CNS depressants (medications like sedatives, sleeping pills, and opioids)—combining kava with them raises the risk of dangerous drowsiness and loss of motor reflexes because kava itself depresses the central nervous system.
Read the full breakdown — every affected drug type, severity by severity
Kava also inhibits liver enzymes (CYP2C19, CYP2C9, and CYP2E1) that break down many medications, which can cause those drugs to build up to higher levels in your body. This affects a broad range of prescriptions—blood thinners, antiarrhythmics, and others metabolized by these pathways.
Additionally, kava may interfere with P-glycoprotein, a transporter that moves certain drugs out of cells, though human evidence is mixed. There are also isolated case reports of serious reactions when kava was combined with haloperidol (an antipsychotic) and ropinirole (a Parkinson's medication).
We could not identify every single medication affected by these enzyme interactions from the data on file. Altogether, these interactions span 1,167 individual medications.
Before you start kava, use the interaction checker below with your exact prescriptions, and talk with your doctor or pharmacist about whether it's safe to combine with what you're taking.
Check your own medications below · Editorial policy · How we use AI
Want to check YOUR meds against Kava?
Ask about interactions with your drugs in plain English — “Can I take it with lisinopril?” — and we find you the answer in seconds, ingredient by ingredient.
Go to the checkerIngredients driving the most interactions
Individual Drug Interactions
The ingredients in Kava interact with 1,166 drugs. Click any drug to see the details.
1 of the 1 ingredient in Kava interact with drugs. Each result below shows which ingredient is responsible. selectively imported Vanuatu Kava
CelecoxibCelebrex, Elyxyb
How Celecoxib interacts with Kava — through 1 ingredient. Tap an ingredient for the detail:
Selectively Imported Vanuatu KavaCytochrome P450 2c9 (cyp2c9) Substrates Moderate
Interaction Summary
Theoretically, kava might increase levels of CYP2C9 substrates.
Read the full Selectively Imported Vanuatu Kava + Celecoxib interactionCeliprololCelicard
How Celiprolol interacts with Kava — through 1 ingredient. Tap an ingredient for the detail:
Selectively Imported Vanuatu KavaP-glycoprotein Substrates Moderate
Interaction Summary
It is unclear if kava inhibits P-glycoprotein (P-gp); research is conflicting.
Read the full Selectively Imported Vanuatu Kava + Celiprolol interactionCeritinibZykadia
How Ceritinib interacts with Kava — through 1 ingredient. Tap an ingredient for the detail:
Selectively Imported Vanuatu KavaHepatotoxic Drugs Moderate
Interaction Summary
Theoretically, using kava with hepatotoxic drugs might increase the risk of liver damage.
Read the full Selectively Imported Vanuatu Kava + Ceritinib interactionCerivastatin SodiumBaycol
How Cerivastatin Sodium interacts with Kava — through 1 ingredient. Tap an ingredient for the detail:
Selectively Imported Vanuatu KavaHepatotoxic Drugs Moderate
Interaction Summary
Theoretically, using kava with hepatotoxic drugs might increase the risk of liver damage.
Read the full Selectively Imported Vanuatu Kava + Cerivastatin Sodium interactionChlorothiazide, MethyldopaAldochlor, Aldoclor 150, Aldoclor 250
How Chlorothiazide, Methyldopa interacts with Kava — through 1 ingredient. Tap an ingredient for the detail:
Selectively Imported Vanuatu KavaHepatotoxic Drugs Moderate
Interaction Summary
Theoretically, using kava with hepatotoxic drugs might increase the risk of liver damage.
Read the full Selectively Imported Vanuatu Kava + Chlorothiazide, Methyldopa interactionChlorpheniramine Maleate, Dextromethorphan HydrobromideCoricidin HBP Cough & Cold, Coricidin II Cough & Cold, Pediatric Vicks Formula 44m Cough & Cold Relief
How Chlorpheniramine Maleate, Dextromethorphan Hydrobromide interacts with Kava — through 1 ingredient. Tap an ingredient for the detail:
Selectively Imported Vanuatu KavaCytochrome P450 3a4 (cyp3a4) Substrates, Cytochrome P450 2e1 (cyp2e1) Substrates +1 Moderate
Interaction Summary
It is unclear if kava inhibits CYP3AA; research is conflicting.
Read the full Selectively Imported Vanuatu Kava + Chlorpheniramine Maleate, Dextromethorphan Hydrobromide interactionChlorpropamideChlorpropam, Diabinese
How Chlorpropamide interacts with Kava — through 1 ingredient. Tap an ingredient for the detail:
Selectively Imported Vanuatu KavaCytochrome P450 2d6 (cyp2d6) Substrates, Hepatotoxic Drugs Moderate
Interaction Summary
It is unclear if kava inhibits CYP1A2; research is conflicting.
Read the full Selectively Imported Vanuatu Kava + Chlorpropamide interactionChlortetracyclineAureomycin
How Chlortetracycline interacts with Kava — through 1 ingredient. Tap an ingredient for the detail:
Selectively Imported Vanuatu KavaHepatotoxic Drugs, P-glycoprotein Substrates Moderate
Interaction Summary
Theoretically, using kava with hepatotoxic drugs might increase the risk of liver damage.
Read the full Selectively Imported Vanuatu Kava + Chlortetracycline interactionCholine Magnesium TrisalicylateTricosal, Trilisate
How Choline Magnesium Trisalicylate interacts with Kava — through 1 ingredient. Tap an ingredient for the detail:
Selectively Imported Vanuatu KavaHepatotoxic Drugs Moderate
Interaction Summary
Theoretically, using kava with hepatotoxic drugs might increase the risk of liver damage.
Read the full Selectively Imported Vanuatu Kava + Choline Magnesium Trisalicylate interactionCholine SalicylateArthropan
How Choline Salicylate interacts with Kava — through 1 ingredient. Tap an ingredient for the detail:
Selectively Imported Vanuatu KavaHepatotoxic Drugs Moderate
Interaction Summary
Theoretically, using kava with hepatotoxic drugs might increase the risk of liver damage.
Read the full Selectively Imported Vanuatu Kava + Choline Salicylate interactionCilostazolPletal
How Cilostazol interacts with Kava — through 1 ingredient. Tap an ingredient for the detail:
Selectively Imported Vanuatu KavaCytochrome P450 2c19 (cyp2c19) Substrates, Cytochrome P450 3a4 (cyp3a4) Substrates Moderate
Interaction Summary
Theoretically, kava might increase levels of CYP2C19 substrates.
Read the full Selectively Imported Vanuatu Kava + Cilostazol interactionCimetidineCimetidine Injection, Tagamet, Tagamet HB
How Cimetidine interacts with Kava — through 1 ingredient. Tap an ingredient for the detail:
Selectively Imported Vanuatu KavaP-glycoprotein Substrates Moderate
Interaction Summary
It is unclear if kava inhibits P-glycoprotein (P-gp); research is conflicting.
Read the full Selectively Imported Vanuatu Kava + Cimetidine interactionCinoxacinCinobac
How Cinoxacin interacts with Kava — through 1 ingredient. Tap an ingredient for the detail:
Selectively Imported Vanuatu KavaHepatotoxic Drugs Moderate
Interaction Summary
Theoretically, using kava with hepatotoxic drugs might increase the risk of liver damage.
Read the full Selectively Imported Vanuatu Kava + Cinoxacin interactionCiprofloxacinCiloxan, Cipro, Cipro IV, Cipro XR, Ciprobay, Otiprio
How Ciprofloxacin interacts with Kava — through 1 ingredient. Tap an ingredient for the detail:
Selectively Imported Vanuatu KavaHepatotoxic Drugs Moderate
Interaction Summary
Theoretically, using kava with hepatotoxic drugs might increase the risk of liver damage.
Read the full Selectively Imported Vanuatu Kava + Ciprofloxacin interactionCisapridePropulsid
How Cisapride interacts with Kava — through 1 ingredient. Tap an ingredient for the detail:
Selectively Imported Vanuatu KavaCytochrome P450 3a4 (cyp3a4) Substrates, P-glycoprotein Substrates Moderate
Interaction Summary
It is unclear if kava inhibits CYP3AA; research is conflicting.
Read the full Selectively Imported Vanuatu Kava + Cisapride interactionCitalopramCelexa
How Citalopram interacts with Kava — through 1 ingredient. Tap an ingredient for the detail:
Selectively Imported Vanuatu KavaCytochrome P450 2c19 (cyp2c19) Substrates, Cytochrome P450 3a4 (cyp3a4) Substrates Moderate
Interaction Summary
Theoretically, kava might increase levels of CYP2C19 substrates.
Read the full Selectively Imported Vanuatu Kava + Citalopram interactionClobetasolClobex, Temovate
How Clobetasol interacts with Kava — through 1 ingredient. Tap an ingredient for the detail:
Selectively Imported Vanuatu KavaP-glycoprotein Substrates Moderate
Interaction Summary
It is unclear if kava inhibits P-glycoprotein (P-gp); research is conflicting.
Read the full Selectively Imported Vanuatu Kava + Clobetasol interactionClomipramineAnafranil, Anafranil SR
How Clomipramine interacts with Kava — through 1 ingredient. Tap an ingredient for the detail:
Selectively Imported Vanuatu KavaCytochrome P450 3a4 (cyp3a4) Substrates, Cytochrome P450 2d6 (cyp2d6) Substrates +3 Moderate
Interaction Summary
It is unclear if kava inhibits CYP3AA; research is conflicting.
Read the full Selectively Imported Vanuatu Kava + Clomipramine interactionClopidogrelPlavix
How Clopidogrel interacts with Kava — through 1 ingredient. Tap an ingredient for the detail:
Selectively Imported Vanuatu KavaCytochrome P450 3a4 (cyp3a4) Substrates, Cytochrome P450 2c9 (cyp2c9) Substrates +1 Moderate
Interaction Summary
It is unclear if kava inhibits CYP3AA; research is conflicting.
Read the full Selectively Imported Vanuatu Kava + Clopidogrel interactionCobicistat, Elvitegravir, Emtricitabine, Tenofovir Alafenamide FumarateGenvoya
How Cobicistat, Elvitegravir, Emtricitabine, Tenofovir Alafenamide Fumarate interacts with Kava — through 1 ingredient. Tap an ingredient for the detail:
Selectively Imported Vanuatu KavaP-glycoprotein Substrates, Cytochrome P450 3a4 (cyp3a4) Substrates +1 Moderate
Interaction Summary
It is unclear if kava inhibits P-glycoprotein (P-gp); research is conflicting.
Read the full Selectively Imported Vanuatu Kava + Cobicistat, Elvitegravir, Emtricitabine, Tenofovir Alafenamide Fumarate interactionColchicineColchicine, Colcrys, Colsalide Improved, Gloperba, Lodoco, Mitigare
How Colchicine interacts with Kava — through 1 ingredient. Tap an ingredient for the detail:
Selectively Imported Vanuatu KavaCytochrome P450 3a4 (cyp3a4) Substrates, P-glycoprotein Substrates Moderate
Interaction Summary
It is unclear if kava inhibits CYP3AA; research is conflicting.
Read the full Selectively Imported Vanuatu Kava + Colchicine interactionColchicine, ProbenecidColBenemid
How Colchicine, Probenecid interacts with Kava — through 1 ingredient. Tap an ingredient for the detail:
Selectively Imported Vanuatu KavaP-glycoprotein Substrates, Cytochrome P450 3a4 (cyp3a4) Substrates Moderate
Interaction Summary
It is unclear if kava inhibits P-glycoprotein (P-gp); research is conflicting.
Read the full Selectively Imported Vanuatu Kava + Colchicine, Probenecid interactionConjugated EstrogensCenestin, Enjuvia, Premarin, Premarin Vaginal Cream
How Conjugated Estrogens interacts with Kava — through 1 ingredient. Tap an ingredient for the detail:
Selectively Imported Vanuatu KavaCytochrome P450 3a4 (cyp3a4) Substrates, P-glycoprotein Substrates Moderate
Interaction Summary
It is unclear if kava inhibits CYP3AA; research is conflicting.
Read the full Selectively Imported Vanuatu Kava + Conjugated Estrogens interactionConjugated Estrogens, Medroxyprogesterone AcetatePremplus, Prempro
How Conjugated Estrogens, Medroxyprogesterone Acetate interacts with Kava — through 1 ingredient. Tap an ingredient for the detail:
Selectively Imported Vanuatu KavaP-glycoprotein Substrates, Cytochrome P450 3a4 (cyp3a4) Substrates Moderate
Interaction Summary
It is unclear if kava inhibits P-glycoprotein (P-gp); research is conflicting.
Read the full Selectively Imported Vanuatu Kava + Conjugated Estrogens, Medroxyprogesterone Acetate interactionConjugated Estrogens, MeprobamatePMB 200, PMB 400
How Conjugated Estrogens, Meprobamate interacts with Kava — through 1 ingredient. Tap an ingredient for the detail:
Selectively Imported Vanuatu KavaCytochrome P450 3a4 (cyp3a4) Substrates, P-glycoprotein Substrates Moderate
Interaction Summary
It is unclear if kava inhibits CYP3AA; research is conflicting.
Read the full Selectively Imported Vanuatu Kava + Conjugated Estrogens, Meprobamate interactionConjugated Estrogens, MethyltestosteronePremarin with Methyltestosterone
How Conjugated Estrogens, Methyltestosterone interacts with Kava — through 1 ingredient. Tap an ingredient for the detail:
Selectively Imported Vanuatu KavaP-glycoprotein Substrates, Cytochrome P450 3a4 (cyp3a4) Substrates +1 Moderate
Interaction Summary
It is unclear if kava inhibits P-glycoprotein (P-gp); research is conflicting.
Read the full Selectively Imported Vanuatu Kava + Conjugated Estrogens, Methyltestosterone interactionCortisone AcetateCortisone Tablets, Cortone
How Cortisone Acetate interacts with Kava — through 1 ingredient. Tap an ingredient for the detail:
Selectively Imported Vanuatu KavaP-glycoprotein Substrates Moderate
Interaction Summary
It is unclear if kava inhibits P-glycoprotein (P-gp); research is conflicting.
Read the full Selectively Imported Vanuatu Kava + Cortisone Acetate interactionCrizotinibXalkori
How Crizotinib interacts with Kava — through 1 ingredient. Tap an ingredient for the detail:
Selectively Imported Vanuatu KavaP-glycoprotein Substrates, Cytochrome P450 3a4 (cyp3a4) Substrates Moderate
Interaction Summary
It is unclear if kava inhibits P-glycoprotein (P-gp); research is conflicting.
Read the full Selectively Imported Vanuatu Kava + Crizotinib interactionCyclophosphamideCytoxan, Neosar
How Cyclophosphamide interacts with Kava — through 1 ingredient. Tap an ingredient for the detail:
Selectively Imported Vanuatu KavaCytochrome P450 2c19 (cyp2c19) Substrates, Hepatotoxic Drugs +1 Moderate
Interaction Summary
Theoretically, kava might increase levels of CYP2C19 substrates.
Read the full Selectively Imported Vanuatu Kava + Cyclophosphamide interactionCyclosporineCequa, Ciclosporine, Gengraf, Neoral, Sandimmune, Verkazia +1 more
How Cyclosporine interacts with Kava — through 1 ingredient. Tap an ingredient for the detail:
Selectively Imported Vanuatu KavaCytochrome P450 3a4 (cyp3a4) Substrates, P-glycoprotein Substrates +1 Moderate
Interaction Summary
It is unclear if kava inhibits CYP3AA; research is conflicting.
Read the full Selectively Imported Vanuatu Kava + Cyclosporine interactionEach ingredient & the kinds of drugs it affects
For each ingredient in Kava with known interactions, here are the types of medications it can affect. Open any type for the detail — or search your exact drug in the checker above.
selectively imported Vanuatu Kava
Cns Depressants
Combining kava with CNS depressants can have additive sedative effects.
Kava has CNS depressant effects. Concomitant use of kava with other CNS depressants can increase the risk of drowsiness and motor reflex depression. Clinical practice guidelines from a joint taskforce of the World Federation of Societies of Biological Psychiatry (WFSBP) and the Canadian Network for Mood and Anxiety Treatments (CANMAT) recommend that CNS depressants, including alcohol and benzodiazepines, not be used with kava.
Alcohol (Ethanol)
Combining kava with alcohol may increase the risk of sedation and/or hepatotoxicity.
Kava has CNS depressant effects. Concomitant use of kava with other CNS depressants can increase the risk of drowsiness and motor reflex depression. Additionally, kava has been associated with over 100 cases of hepatotoxicity. There is some concern that kava can adversely affect the liver, especially when used in combination with hepatotoxic drugs. Clinical practice guidelines from a joint taskforce of the World Federation of Societies of Biological Psychiatry (WFSBP) and the Canadian Network for Mood and Anxiety Treatments (CANMAT) recommend that alcohol not be used with kava.
Cytochrome P450 2C19 (Cyp2C19) Substrates
Theoretically, kava might increase levels of CYP2C19 substrates.
In vitro research shows that kava significantly inhibits CYP2C19 enzymes. This effect has not yet been reported in humans.
Cytochrome P450 2C9 (Cyp2C9) Substrates
Theoretically, kava might increase levels of CYP2C9 substrates.
In vitro research shows that kava significantly inhibits CYP2C9 enzymes. This effect has not yet been reported in humans.
Cytochrome P450 2E1 (Cyp2E1) Substrates
Kava might increase levels of CYP2E1 substrates.
In a clinical study in healthy volunteers, taking kava 1000 mg twice daily (containing a daily dose of 138 mg kavalactones) for 28 days inhibited the metabolism of CYP2E1 substrates.
Haloperidol (Haldol)
Combining kava and haloperidol might increase the risk of cardiovascular adverse effects and hypoxia.
Atrial flutter and hypoxia has been reported for a patient who received intramuscular injections of haloperidol and lorazepam after using kava orally. The side effects were attributed to kava-induced inhibition of CYP2D6, but might also have been related to additive adverse effects with the concomitant use of haloperidol, lorazepam, and kava.
Hepatotoxic Drugs
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.
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.
Ropinirole (Requip)
Taking kava with ropinirole might increase the risk for dopaminergic toxicity.
A case of visual hallucinations and paranoid delusions has been reported for a patient who used kava in combination with ropinirole. The adverse effects were attributed to kava-induced inhibition of CYP1A2, which may have reduced the metabolism of ropinirole, resulting in excessive dopaminergic stimulation.
Cytochrome P450 1A2 (Cyp1A2) Substrates
It is unclear if kava inhibits CYP1A2; research is conflicting.
Although in vitro research and a case report suggest that kava inhibits CYP1A2, more robust clinical evidence shows that kava has no effect on CYP1A2. 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 CYP1A2 activity.
Cytochrome P450 2D6 (Cyp2D6) Substrates
It is unclear if kava inhibits CYP1A2; research is conflicting.
In vitro research shows that kava extract significantly inhibits CYP2D6. However, clinical research shows that kava does not affect the metabolism of CYP2D6 substrates in humans.
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.
Brand information
Manufacturer and brand details for Kava, from the product label.
Thymely Solutions
See all Thymely Solutions products- Name
- Thymely Solutions
- Street Address
- 104 N Court St.
- City
- Fairfield
- State
- IA
- ZipCode
- 52556
- Phone Number
- (641) 472-9815
Kava by Thymely Solutions: Common Questions
Does Kava by Thymely Solutions interact with any medications?
How can one product interact with so many drugs?
Where does this information come from?
Will kava help my anxiety?
Is kava safe if I take other medications?
What are the common side effects?
Can I take kava while pregnant or breastfeeding?
Is the liver damage from kava common?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
Not sure if Kava is safe with your meds?
Our pharmacists answer your medication & supplement questions — free.
Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.
The Full Monographs Behind Kava’s Ingredients
Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.
Sources & How We Checked
Kava's label data comes from the NIH Dietary Supplement Label Database; the ingredient interaction data is from the Natural Medicines database, reviewed by our pharmacists.
- NIH Dietary Supplement Label Database (DSLD) — The official product label on file for this supplement.
- Natural Medicines (Therapeutic Research Center) — Evidence-graded clinical reference behind the ingredient interaction data.
Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.
The 71 references behind this product’s interaction data
Every citation that drives the interaction findings for this product’s ingredients, from the evidence-graded Natural Medicines (TRC Healthcare) database. Open an ingredient to browse its citations — links open the study on PubMed or the publisher’s site.
Kava 71 references
- Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
- Strahl S, Ehret V, Dahm HH, Maier KP. [Necrotizing hepatitis after taking herbal medication]. Dtsch Med Wochenschr 1998;123:1410-4.
- Spillane PK, et al. Neurological manifestations of kava intoxication. Med J Aust 1997;167:172-3. PubMed
- Swensen JN. Man convicted of driving under the influence of kava. Salt Lake City, UT: Deseret News, 1996.
- Pittler MH, Ernst E. Efficacy of kava extract for treating anxiety: systematic review and meta-analysis. J Clin Psychopharmacol 2000;20:84-9. PubMed
- Volz HP, Kieser M. Kava-kava extract WS 1490 versus placebo in anxiety disorders--a randomized placebo-controlled 25-week outpatient trial. Pharmacopsychiatry 1997;30:1-5. PubMed
- Heinze HJ, Munthe TF, Steitz J, Matzke M. Pharmacopsychological effects of oxazepam and kava-extract in a visual search paradigm assessed with event-related potentials. Pharmacopsychiatry 1994;27:224-30. PubMed
- Munte TF, Heinze HJ, Matzke M, Steitz J. Effects of oxazepam and an extract of kava roots (Piper methysticum) on event-related potentials in a word recognition task. Neuropsychobiology 1993;27:46-53.
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