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Dietary supplement

Kava Extract Powder Ingredients & Drug Interactions

by Materia Organica

Kava Extract Powder label
See full label image
Powder 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 Extract Powder 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 Extract Powder is a dietary supplement by Materia Organica 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 Extract, Powder. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Kava Extract Powder by Materia Organica

Ask about any prescription or over-the-counter medication and we check it for interactions with Kava Extract Powder by Materia Organica — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Kava Extract Powder by Materia Organica

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 Jul 11, 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 a single active ingredient: kava extract powder. Kava is a plant root traditionally used in the South Pacific; the extract concentrates its active compounds (kavalactones) into powder form.

There are no other inactive ingredients listed.

Does it work?

Leans against
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
Leans against

The strongest graded evidence we hold for the stated purpose leans against a benefit.

Why this rating?
  • The label markets this product for: anxiety and stress relief.
  • We looked for evidence on: Generalized anxiety disorder (GAD), Stress, Insomnia, 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 for kava is mixed and limited. For generalized anxiety, research rates it as possibly ineffective — meaning the data doesn't support that it works reliably.

For insomnia and sexual arousal, there isn't enough reliable evidence in our data to rate it either way. For epilepsy, the evidence is also insufficient to establish whether it helps.

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 when taken by mouth, but comes with important caveats. The most common side effects are drowsiness, dry mouth, dizziness, stomach upset, headache, memory problems, and tremors.

Serious liver injury (hepatotoxicity) is rare but well documented — over 100 cases have been reported worldwide, particularly with heavy or prolonged use. Some people show symptoms of liver damage after as little as 3 to 4 weeks.

Kava is not safe during pregnancy and should be avoided. It should also be avoided while breastfeeding because safety data is lacking and the compound may pass 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 taking kava, double-check if you use any CNS depressants (sleeping pills, sedatives, opioids, benzodiazepines), blood thinners, heart medications (including digoxin), antipsychotics or Parkinson's medications, seizure drugs, or any other drug metabolized by your liver. Also flag any medication that can damage the liver.

The interaction list is long — run your exact medications through the checker on this page.

Check your own medication Run your meds through the checker above

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 might appeal to someone looking for anxiety or sleep support, but the evidence doesn't strongly back either use, and the risk of liver damage is real — especially with long-term use. If you take any medication for sleep, pain, mood, heart rhythm, blood thinning, or seizures, you need to check this product with your pharmacist or doctor first.

Pregnancy and breastfeeding are reasons to skip 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 Jul 24, 2025.

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 Extract Powder, straight from the product label.

Brand Materia Organica
Net contents 3.5 Ounce(s); 100 Gram(s)
Market status On market
Date entered into DSLD Jul 24, 2025
DSLD ID 332152
Product type Botanical
Supplement form Powder
Dietary claims / uses All Other
Intended target group(s) Vegan, Vegetarian, Adult (18 - 50 Years), Kosher, Organic, Dairy Free
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 Extract Powder by Materia Organica, 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:
350 mg
Maximum serving Sizes:
350 mg
Servings per container
285
IngredientAmount% DV
Kava Extract, Powder350 mg--

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.
FDA Statement of Identity

Dietary Supplement

Formula

Star-K (Kosher)

Kosher Star-K Kosher

This Kava Extract Powder is water-soluble, rendering it much more bioavailable than ordinary powders or even extract powders. 100% Kava

Seals/Symbols

Star-K (Kosher)

General Statements

Materia Organica primarily sells bulk ingredients to manufacturers and brand owners.

Formulation

Water-soluble CO2 extracted (no petroleum solvents used) Vacuum dried to retain micronutrients (not spray dried) Better bioavailability and potency

No additives, fillers, or other ingredients Non-GMO, vegetarian/vegan, non-irradiated

Certified Organic by CCOF

Product of India Tested in independent 3rd-party US labs.

Suggested/Recommended/Usage/Directions

Directions: Mix 350 mg (about 1/8 teaspoon) into water, milk, tea, or a smoothie.

Precautions

Warning: Kava use can have side effects, including dizziness, drowsiness, and headache. It is not recommended to take Kava continuously without breaks. Long-term use of kava may cause liver damage. It is very important to prepare kava correctly to avoid liver damage. Individuals with liver problems should avoid using kava.

Kava may interact with medications, such as antidepressants, anti-anxiety medications, and sedatives.

Keep out of reach of children.

Storage

Store in sealed container in a dry, cool area.

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

See for yourself

Kava Extract Powder by Materia Organica label

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

Kava Extract Powder 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 Extract Powder by Materia Organica

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

Serving size350 mg Dosage formPowder Servings per container285 Amounts shown are per serving.

Kava Extract, Powder

Interacts with
1,166 drugs
350 mg per serving

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 Extract, Powder monograph & interactions
Interaction report

Kava Extract Powder by Materia Organica Drug Interactions

Want to check YOUR meds against Kava Extract Powder?

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 Extract, Powder 1,166

Individual Drug Interactions

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

1 of the 1 ingredient in Kava Extract Powder interact with drugs. Each result below shows which ingredient is responsible. Kava Extract, Powder

Each ingredient & the kinds of drugs it affects

For each ingredient in Kava Extract Powder 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 Extract, Powder12 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 Extract, Powder full monograph & interactions
The maker

Brand information

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

Materia Organica

See all Materia Organica products
Name
Materia Organica
City
Quitman
State
TX
ZipCode
75783
Phone Number
800-613-6311
Web Address
www.MateriaOrganica.com
Pharmacist Counseling Corner

Kava Extract Powder by Materia Organica: Common Questions

Does Kava Extract Powder by Materia Organica interact with any medications?
Yes. Based on its ingredients, Kava Extract Powder 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 Extract Powder 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.
Can I take kava with my antidepressant or anti-anxiety medication?
Many of those drugs are CNS depressants, and combining them with kava adds to drowsiness and reflex problems. You need to check your specific medication with your pharmacist before starting kava — don't combine them without professional guidance.
Is kava safe to use long-term?
Kava has been linked to over 100 cases of liver injury, especially with heavy or prolonged use. Symptoms can show up after as little as 3 to 4 weeks. We'd recommend discussing duration and monitoring with your doctor if you're considering regular use.
What are the most common side effects?
Drowsiness, dry mouth, dizziness, stomach upset, headache, memory problems, and tremors. A few people have also reported involuntary facial movements or tremor similar to Parkinson's symptoms, though that's less common.
Does kava actually help anxiety?
The evidence in our data rates kava as possibly ineffective for generalized anxiety — meaning the science doesn't reliably show it works for that purpose. Talk with your pharmacist about better-studied options.
Can I use kava if I'm pregnant or breastfeeding?
No. Kava is not safe during pregnancy and should be avoided. It should also be avoided while breastfeeding because we don't have safety data and it may pass to your infant.

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

Not sure if Kava Extract Powder 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 Extract Powder label
Go deeper

The Full Monographs Behind Kava Extract Powder’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 Extract Powder'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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  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
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  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
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  9. Wheatley D. Stress-induced insomnia treated with kava and valerian: singly and in combination. Hum Psychopharmacol 2001;16:353-6. PubMed
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  16. Liver Toxicity With Kava. Pharmacist's Letter/Prescriber's Letter. January 2001.
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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.
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  27. Schulze J, Raasch W, Siegers CP. Toxicity of kava pyrones, drug safety and precautions--a case study. Phytomedicine 2003;10:68-73.. PubMed
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  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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  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
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  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.
  53. Johnson D, Frauendorf A, Stecker K, and et al. Neurophysiological active profile and tolerance of kava extract WS 1490, A pilot study with randomized evaluation. TW Neurolgie Psychiatrie 1991;5(6):349-354.
  54. Keller F and Klohs M. A review of the chemistry and pharmacology of the constituents of Piper methysticum. Lloydia 1963;26:1-15.
  55. Siegers CP, Honold E, Krall B, and et al. Results of the drug monitoring L 1090 with Laitan capsules. Arztl Forsch 1992;39:7-11.
  56. Chanwai, L. G. Kava toxicity. Emergency Medicine 2002;12:142-145.
  57. Leung, N. Acute urinary retention secondary to kava ingestion. Emerg Med Australas 2004;16(1):94. PubMed
  58. Teschke R. Kava hepatotoxicity: pathogenetic aspects and prospective considerations. Liver Int 2010;30(9):1270-9. PubMed
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See these in context on the Kava monograph →

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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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