Major interaction on record — check this product against your medications before combining. Check your meds →
Dietary supplement

Kava Kava Extract 1000 mg Ingredients & Drug Interactions

by Double Wood Supplements

Kava Kava Extract 1000 mg label
See full label image
Capsule Category: Botanical
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Kava Kava Extract 1000 mg 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

The interaction bottom line Most serious interaction: Major

Kava Kava Extract 1000 mg is a dietary supplement by Double Wood Supplements 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 Kava Kava extract. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Kava Kava Extract 1000 mg by Double Wood Supplements

Ask about any prescription or over-the-counter medication and we check it for interactions with Kava Kava Extract 1000 mg by Double Wood Supplements — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Kava Kava Extract 1000 mg by Double Wood Supplements

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.

From our pharmacy team — supplement deep dive

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Aug 13, 2026

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 1 of its 1 active ingredient.
  • No proprietary blends here — you can verify the dose of every single component.

This product contains one active ingredient: kava kava extract at 1000 mg per capsule. Kava is a plant from the South Pacific whose root has been used traditionally for relaxation and social settings.

The capsule itself is made from hypromellose and microcrystalline cellulose, which are inert ingredients that help hold the extract together.

Does it work?

Not established
Evidence for Intended Use · database check
By FDA rules, dietary supplements can’t claim to treat, cure, or prevent disease — so labels speak in careful marketing language. We discern each product’s intended use from its name, label claims, and label statements, then grade the clinical evidence for that use. How these ratings are computed
Not established

The graded evidence we hold for these ingredients covers different conditions than the ones this product is marketed for, so there's no established rating for its stated use — see Kava's own graded uses on its monograph.

Why this rating?
  • The label markets this product for: supports healthy stress levels and sleep.
  • We looked for evidence on: Generalized anxiety disorder (GAD), Insomnia, Stress, Menopausal symptoms, relaxation, restlessness.
  • The closest evidence on file: Kava is rated "Possibly Ineffective" for Generalized anxiety disorder (GAD) (Natural Medicines).
  • Also on file: Kava is rated "Insufficient Reliable Evidence To Rate" for Insomnia, Menopausal symptoms, Stress.

The evidence on kava for the conditions studied is mixed. For generalized anxiety disorder, the data we have suggests kava is possibly ineffective.

For insomnia and sexual arousal, there simply isn't enough reliable evidence yet to know whether it works. The studies we hold data on don't support a strong case for anxiety relief, so it's worth having realistic expectations if that's why you're considering it.

The evidence, ingredient by ingredient Kava

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

Adverse-effect, pregnancy, and general safety data are on file for most of these ingredients.

Why this rating?
  • We hold adverse-effect (side-effect) data for 1 of the 1 matched ingredient.
  • Pregnancy & breastfeeding safety ratings cover 1 of 1.
  • General safety write-ups exist for 1 of 1.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Kava is generally well tolerated at normal doses, and common side effects—drowsiness, dry mouth, dizziness, headache, and memory issues—tend to be mild. The real caution is liver injury.

Over 100 cases of hepatotoxicity have been reported worldwide, and in susceptible people symptoms can appear in as little as 3–4 weeks. You may also experience tremors (one trial found a 3.2-fold higher risk compared to placebo), involuntary mouth movements, or parkinsonian-like symptoms.

Kava is not safe in pregnancy and should be avoided while breastfeeding due to lack of safety data and the risk of transfer to your infant.

Side effects, ingredient by ingredient Kava

Meds to double-check

Major interaction found
Known Interaction Concern · database check
Major identified

At least one ingredient has a documented Major-severity interaction. Check your medications for a personalized result.

Why this rating?
  • 1 of the 1 matched ingredient can interact with medications — Kava.
  • The most serious interaction on file is rated Major.
  • For scale: 1,167 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Before you take this product, double-check any CNS depressants (sleep aids, anti-anxiety medications, opioids, or alcohol)—combining them with kava can cause serious drowsiness and impaired reflexes. Also flag any drugs your liver metabolizes, particularly haloperidol and ropinirole, which have had rare serious side effects reported with kava.

And if you're on any medication that's hard on the liver itself, talk to your pharmacist or doctor first.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with no established evidence rating for its marketed use. Major medication interactions have been identified, and safety information is well characterized.

Kava might appeal to you if you're looking for an herbal relaxation aid, but the liver-injury risk and interaction potential mean it's not a casual add-on. If you take any prescription medications, especially sedating drugs or anything that affects how your liver works, you need to check with your doctor or pharmacist before starting.

Pregnant women and breastfeeding mothers should avoid it entirely.

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 Sep 24, 2021.

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

At a glance

General information

Key facts about Kava Kava Extract 1000 mg, straight from the product label.

Brand Double Wood Supplements
Barcode (UPC) 859793007679
Net contents 120 Capsule(s)
Market status On market
Date entered into DSLD Sep 24, 2021
DSLD ID 255598
Product type Botanical
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Women (not pregnant or lactating)
From the label
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 Kava Extract 1000 mg by Double Wood Supplements, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
2 Capsule(s)
Maximum serving Sizes:
3 Capsule(s)
Servings per container
60
UPC/BARCODE
859793007679
IngredientAmount% DV
Kava Kava extract1000 mg--

Other ingredients: Hypromellose, Microcrystalline Cellulose

Tap any ingredient to jump to its full detail below.

Label statements
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.
Formula

Directions: Kava Kava is an extract prepared from Piper methysticum commonly known as kava. It has been traditionally used to brew tea to promote healthy stress levels and support healthy sleep. This supplement provides the same benefits of the tea in a convenient capsule form. Kava is a potent supplement and should not be combined with alcohol or certain prescription medications.

1000 mg per serving

Suggested/Recommended/Usage/Directions

Suggested Use: As a dietary supplement, take 2 capsules per day on an empty stomach. Do not exceed 3 capsules in one day.

Storage

Storage: Store in a cool, dark place. Do not freeze or expose to moisture or heat above room temperature.

Formulation

Supports healthy stress levels Promotes relaxation

FDA Statement of Identity

Dietary Supplement

Precautions

Warning: Consult your physician before use.

Do not use Kava Kava if you are pregnant, nursing, or are under 18 years of age.

Do not use Kava Kava if you are pregnant, nursing, or are under 18 years of age.

Discontinue use and consult your doctor immediately if any adverse reactions or side effects occur. Do not use Kava Kava and operate heavy machinery until you know how it affects you.

Keep out of reach of children.

Do not exceed 3 capsules per day.

FDA Disclaimer Statement

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

Is this label outdated? Report a formula or label change and our pharmacy team will review it.

See for yourself

Kava Kava Extract 1000 mg by Double Wood Supplements label

The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.

Kava Kava Extract 1000 mg label

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)
What’s inside

The Ingredients in Kava Kava Extract 1000 mg by Double Wood Supplements

This is the 1 active ingredient this product is made of. Select it to open its full monograph.

Serving size2 Capsule(s) Dosage formCapsule Servings per container60 Amounts shown are per serving.

Kava Kava extract

Interacts with
1,166 drugs
1000 mg per serving Form: Total Kavalactones

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 Kava extract monograph & interactions

Other (inactive) ingredients: Hypromellose, Microcrystalline Cellulose. These complete the product’s ingredient list but are not active constituents.

Interaction report

Kava Kava Extract 1000 mg by Double Wood Supplements Drug Interactions

Want to check YOUR meds against Kava Kava Extract 1000 mg?

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 checker
1,166Drugs
248 Major 577 Moderate 341 Minor

Ingredients driving the most interactions

Kava Kava extract 1,166

Individual Drug Interactions

The ingredients in Kava Kava Extract 1000 mg interact with 1,166 drugs. Click any drug to see the details.

1 of the 1 ingredient in Kava Kava Extract 1000 mg interact with drugs. Each result below shows which ingredient is responsible. Kava Kava extract

Each ingredient & the kinds of drugs it affects

For each ingredient in Kava Kava Extract 1000 mg 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.

Kava Kava extract12 drug types · 1,166 drugs

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.

Likelihood Probable Evidence A
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.

Likelihood Possible Evidence A
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.

Likelihood Possible Evidence D
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.

Likelihood Possible Evidence D
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.

Likelihood Probable Evidence B
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.

Likelihood Possible Evidence D
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.

Likelihood Possible Evidence D
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.

Likelihood Possible Evidence D
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.

Likelihood Possible Evidence D
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.

Likelihood Unlikely Evidence B
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.

Likelihood Unlikely Evidence B
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.

Likelihood Unlikely Evidence B
Kava Kava extract full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Kava Kava Extract 1000 mg, from the product label.

Double Wood Supplements

See all Double Wood Supplements products
Name
Double Wood LLC
Street Address
3510 Scotts Ln Ste 219
City
Philadelphia
State
PA
ZipCode
19129-1573
Web Address
www.doublewoodsupplements.com
Pharmacist Counseling Corner

Kava Kava Extract 1000 mg by Double Wood Supplements: Common Questions

Does Kava Kava Extract 1000 mg by Double Wood Supplements interact with any medications?
Yes. Based on its ingredients, Kava Kava Extract 1000 mg has a known interaction with 1,166 medications, including 248 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Kava Kava Extract 1000 mg contains a single active ingredient, and that one ingredient can interact with many different medications on its own. We check it against each medication and show the mechanism responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Will kava actually help my anxiety?
The evidence on kava for generalized anxiety disorder suggests it may be ineffective. While kava is used traditionally for relaxation, the clinical studies we have don't show a strong case for treating anxiety, so it's worth discussing with your doctor whether it's the right choice for you.
Can I take kava if I'm pregnant or breastfeeding?
No. Kava is not considered safe during pregnancy and should be avoided. While breastfeeding, it should also be avoided because there isn't enough safety data and it may pass into breast milk and affect your infant.
What are the most common side effects?
The most common side effects are drowsiness, dry mouth, dizziness, headache, and memory problems. Most people tolerate kava well at normal doses, but tremors and involuntary mouth movements have also been reported.
Is the liver damage risk real?
Yes, it's a real concern. Over 100 cases of liver injury linked to kava have been reported worldwide, especially with excessive or long-term use. In susceptible people, symptoms can appear within 3–4 weeks. That's why kava is banned or restricted in some countries.
Can I take kava with my sleep medication?
No. Kava is a sedative itself, so combining it with sleep aids or any other CNS depressants can cause dangerous levels of drowsiness and impaired reflexes. Check with your doctor or pharmacist before taking it.
What's actually in this capsule?
Each capsule contains 1000 mg of kava kava extract—the active ingredient—plus hypromellose and microcrystalline cellulose, which are inert materials that help form the capsule.

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

Not sure if Kava Kava Extract 1000 mg is safe with your meds?

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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.

Kava Kava Extract 1000 mg label
Go deeper

The Full Monographs Behind Kava Kava Extract 1000 mg’s Ingredients

Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.

Herb & supplement monograph

Kava

Interacts with 1,166 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, kava has been linked to rare but serious...

Read the full Kava monograph →
Sources

Sources & How We Checked

Kava Kava Extract 1000 mg'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.

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
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  2. Strahl S, Ehret V, Dahm HH, Maier KP. [Necrotizing hepatitis after taking herbal medication]. Dtsch Med Wochenschr 1998;123:1410-4.
  3. Spillane PK, et al. Neurological manifestations of kava intoxication. Med J Aust 1997;167:172-3. PubMed
  4. Swensen JN. Man convicted of driving under the influence of kava. Salt Lake City, UT: Deseret News, 1996.
  5. Pittler MH, Ernst E. Efficacy of kava extract for treating anxiety: systematic review and meta-analysis. J Clin Psychopharmacol 2000;20:84-9. PubMed
  6. 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
  7. 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
  8. 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.
  9. Wheatley D. Stress-induced insomnia treated with kava and valerian: singly and in combination. Hum Psychopharmacol 2001;16:353-6. PubMed
  10. Schelosky L, Raffaup C, Jendroska K, Poewe W. Kava and dopamine antagonism. J Neurol Neurosurg Psychiatry 1995;58:639-40. PubMed
  11. Norton SA, Ruze P. Kava dermopathy. J Am Acad Dermatol 1994;31:89-97.
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  13. Mathews JD, Riley MD, Fejo L, et al. Effects of heavy usage of kava on physical health: Summary of a pilot survey in an aboriginal community. Med J Aust 1988;148:548-55.
  14. Escher M, Desmeules J, Giostra E, Mentha G. Hepatitis associated with Kava, a herbal remedy for anxiety. BMJ 2001;322:139.
  15. Russmann S, Lauterburg BH, Helbling A. Kava hepatotoxicity [letter]. Ann Intern Med 2001;135:68-9.
  16. Liver Toxicity With Kava. Pharmacist's Letter/Prescriber's Letter. January 2001.
  17. 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.
  18. Meseguer E, Taboada R, Sanchez V, et al. Life-threatening parkinsonism induced by kava-kava. Mov Disord 2002;17:195-6. PubMed
  19. Ruze P. Kava-induced dermopathy: a niacin deficiency? Lancet 1990;335:1442-5. PubMed
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  21. Bilia AR, Gallori S, Vincieri FF. Kava-kava and anxiety: growing knowledge about the efficacy and safety. Life Sci 2002;70:2581-97. PubMed
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  23. 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
  24. Logan JL, Ahmed J. Critical hypokalemic renal tubular acidosis due to Sjogren's syndrome: association with the purported immune stimulant echinacea. Clin Rheumatol 2003;22:158-9.
  25. Teschke R, Gaus W, Loew D. Kava extracts: safety and risks including rare hepatotoxicity. Phytomedicine 2003;10:440-6. PubMed
  26. Schmidt P, Boehncke WH. Delayed-type hypersensitivity reaction to kava-kava extract. Contact Dermatitis 2000;42:363-4.
  27. Schulze J, Raasch W, Siegers CP. Toxicity of kava pyrones, drug safety and precautions--a case study. Phytomedicine 2003;10:68-73.. PubMed
  28. Pittler MH, Ernst E. Kava extract for treating anxiety. Cochrane Database Syst Rev 2003;(1):CD003383.
  29. Cairney S, Maruff P, Clough AR, et al. Saccade and cognitive impairment associated with kava intoxication. Hum Psychopharmacol 2003;18:525-33. PubMed
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  31. Gow PJ, Connelly NJ, Hill RL, et al. Fatal fulminant hepatic failure induced by a natural therapy containing kava. Med J Aust 2003;178:442-3. PubMed
  32. 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
  33. 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
  34. 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
  35. 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
  36. Gurley BJ, Swain A, Hubbard MA, et al. Clinical assessement of CYP2D6-mediated herb-drug interactions in humans: Effects of milk-thistle, black cohosh, goldenseal, kava kava, St. John's wort, and Echinacea. Mol Nutr Food Res 2008;52:755-63.
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  38. Bodkin R, Schneider S, Rekkerth D, et al. Rhabdomyolysis associated with kava ingestion. Am J Emerg Med 2012;30:635.el-3. PubMed
  39. Donadio V, Bonsi P, Zele I, et al. Myoglobinuria after ingestion of extracts of guarana, Ginkgo biloba and kava. Ginkgo biloba and kava. Neurol Sci 2000;21:124. PubMed
  40. Sarris J, Kavanagh DJ, Byrne G, et al. The Kava Anxiety Depression Spectrum Study (KADSS): a randomized, placebo-controlled crossover trial using an aqueous extract of Piper methysticum. Psychopharmacology 2009;205:399-407. PubMed
  41. Hannam S, Murray M, Romani L, Tuicakau M, J Whitfeld M. Kava dermopathy in Fiji: an acquired ichthyosis? Int J Dermatol 2014;53(12):1490-4. PubMed
  42. Huynh JC, Asgari MM, Moore MM. Sebotropic eruption associated with use of oral kava kava supplement. Clin Exp Dermatol 2014;39(7):816-8. PubMed
  43. Teschke R, Sarris J, Schweitzer I. Kava hepatotoxicity in traditional and modern use: the presumed Pacific kava paradox hypothesis revisited. Br J Clin Pharmacol 2012;73(2):170-4. PubMed
  44. Scherer, J. Kava-kava extract in anxiety disorders: an outpatient observational study. Adv.Ther. 1998;15(4):261-269.
  45. Humberston, C. L., Akhtar, J., and Krenzelok, E. P. Acute hepatitis induced by kava kava. J Toxicol.Clin Toxicol. 2003;41(2):109-113. PubMed
  46. Schmidt, M. Are kavalactones the hepatotoxic principle of kava extracts? The pitfalls of the glutathione theory. J Altern Complement Med 2003;9(2):183-187. PubMed
  47. Stickel, F., Baumuller, H. M., Seitz, K., Vasilakis, D., Seitz, G., Seitz, H. K., and Schuppan, D. Hepatitis induced by Kava (Piper methysticum rhizoma). J Hepatol. 2003;39(1):62-67. PubMed
  48. Grace, R. Kava-induced urticaria. J Am Acad Dermatol 2005;53(5):906. PubMed
  49. Christl, S. U., Seifert, A., and Seeler, D. Toxic hepatitis after consumption of traditional kava preparation. J.Travel.Med. 2009;16(1):55-56. PubMed
  50. Teschke, R., Genthner, A., and Wolff, A. Kava hepatotoxicity: comparison of aqueous, ethanolic, acetonic kava extracts and kava-herbs mixtures. J.Ethnopharmacol. 6-25-2009;123(3):378-384. PubMed
  51. Jappe, U., Franke, I., Reinhold, D., and Gollnick, H. P. Sebotropic drug reaction resulting from kava-kava extract therapy: a new entity? J Am Acad Dermatol. 1998;38(1):104-106. PubMed
  52. Gessner B and Cnota P. Extract of the kava-kava rhizome in comparison with diazepam and placebo. Z Phytother 1994;15(1):30-37.
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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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