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

Kava Kava Extract 250 mg Ingredients & Drug Interactions

by NOW

Kava Kava Extract 250 mg label
See full label image
Capsule Category: Botanical
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 9, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Kava Kava Extract 250 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 250 mg is a dietary supplement by NOW with 2 active ingredients. Its ingredients are commonly taken for fatigue and low energy, physical and athletic performance, stress resistance (adaptogen).Based on those ingredients, 1,348 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Kava Kava Root Extract, Eleuthero. 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 250 mg by NOW

Ask about any prescription or over-the-counter medication and we check it for interactions with Kava Kava Extract 250 mg by NOW — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of Kava Kava Extract 250 mg by NOW

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 2 of its 2 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

This product contains 2 active ingredients: eleuthero and kava kava root extract, each at 250 mg per capsule. Eleuthero is an adaptogenic herb traditionally used to support energy and stress resilience, while kava kava is a botanical known for its kavalactone compounds, which are believed to promote relaxation.

The capsule also contains several inactive ingredients — cellulose (powder), magnesium stearate, and silica — which are common binders and flow agents.

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.

Why this rating?
  • The label markets this product for: relaxation and stress relief.
  • We looked for evidence on: Generalized anxiety disorder (GAD), Stress, Insomnia, Menopausal symptoms, Anxiety, 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.
  • Also on file: Eleuthero is rated "Insufficient Reliable Evidence To Rate" for Stress.

The evidence for these ingredients is mixed and limited. Eleuthero is rated possibly effective only for genital herpes; for other conditions like fatigue, bone health, and bipolar disorder, the evidence isn't established well enough to rate.

Kava is rated possibly ineffective for generalized anxiety disorder, and for insomnia and sexual function the evidence is insufficient. Neither ingredient has strong clinical proof of benefit for most uses people buy them for.

The evidence, ingredient by ingredient Eleuthero 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 2 of the 2 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 2 of 2.
  • General safety write-ups exist for 2 of 2.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Eleuthero is generally well tolerated short-term, but long-term safety data is sparse. You should avoid it during pregnancy and while breastfeeding — there isn't enough safety data.

Common side effects include diarrhea, nausea, headache, and gastrointestinal upset; some people report nervousness, anxiety, or irritability, especially at higher doses. Eleuthero may also raise blood pressure.

Kava is similarly well tolerated short-term but carries a more serious caution: it's been linked to over 100 cases of liver injury, sometimes after just 3–4 weeks of use. Symptoms include yellowed skin and eyes.

You should avoid kava during pregnancy and breastfeeding. Common side effects are drowsiness, dizziness, headache, and memory problems; rarely, it can cause tremors or parkinsonian-like movements.

Side effects, ingredient by ingredient Eleuthero 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?
  • 2 of the 2 matched ingredients can interact with medications — Kava, Eleuthero.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs; diabetes medications; heart-rhythm medications.
  • For scale: 1,349 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 this, double-check with your pharmacist if you use central nervous system depressants (sedatives, sleep aids, opioid pain relievers) — kava's Major interaction here can make drowsiness and motor impairment worse. Also flag any blood thinners, diabetes medications, digoxin, haloperidol, or ropinirole, plus any drug that stresses your liver.

If you take medications broken down by your liver's CYP2C19, CYP2C9, or CYP2E1 systems, those need review too.

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.

This product is not for everyone. If you take a blood thinner, diabetes medication, digoxin, or anything that depresses your central nervous system, talk to your pharmacist first — the interactions are real.

Long-term use isn't well studied, and kava's liver risk is a genuine concern, especially over weeks or months. If you're pregnant or breastfeeding, skip it entirely.

Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI

Assessment coverage: 2 of 2 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Oct 24, 2024.

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 250 mg, straight from the product label.

Brand NOW
Barcode (UPC) 733739047168
Net contents 60 Veg Capsule(s)
Market status On market
Date entered into DSLD Oct 24, 2024
DSLD ID 314403
Product type Botanical
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Vegan, Vegetarian, Adult (18 - 50 Years), Kosher, Women (not pregnant or lactating), Gluten 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 Kava Extract 250 mg by NOW, 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:
1 Veg. Capsule(s)
Maximum serving Sizes:
1 Veg. Capsule(s)
Servings per container
60
UPC/BARCODE
733739047168
IngredientAmount% DV
Eleuthero100 mg--
Kava Kava Root Extract250 mg--

Other ingredients: Cellulose, Cellulose, Powder, Magnesium Stearate, Silica

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.
Suggested/Recommended/Usage/Directions

Suggested Usage: Take 1 capsule 1 to 2 times daily as needed. Daily usage not to exceed 4 weeks.

Precautions

Daily usage not to exceed 4 weeks.

Caution: US FDA advises that a potential risk of rare, but severe, liver injury may be associated with kava-containing dietary supplements. Stop use and see a doctor if you develop symptoms that may signal liver problems (e.g., unexplained fatigue, abdominal pain, loss of appetite, fever, vomiting, dark urine, pale stools, yellow eyes or skin).

Ask a healthcare professional before use if you have or have had liver problems, frequently use alcoholic beverages, or are taking any medication.

Not for use by persons under 18 years of age, or by pregnant or breast feeding women.

Not for use by persons under 18 years of age, or by pregnant or breast feeding women.

Not for use with alcoholic beverages. Excessive use or use with products that cause drowsiness may impair your ability to operate a vehicle or heavy equipment.

Do Not Eat Freshness Packet. Keep in Bottle.

Not manufactured with yeast, wheat, gluten, soy, milk, egg, fish, shellfish or tree nut ingredients. Produced in a GMP facility that processes other ingredients containing these allergens.

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.

Formulation

Natural color variation may occur in this product.

Relaxation Herbal Relaxing Blend

Vegetarian/Vegan

Non-GMO Not manufactured with yeast, wheat, gluten, soy, milk, egg, fish, shellfish or tree nut ingredients.

Product of Canada.

Formula

30% Kavalactones

Triangle K (Kosher)

FDA Statement of Identity

A Dietary Supplement

General Statements

Botanicals/Herbs Family owned since 1968.

Please Recycle

Storage

Do not eat freshness packet. Keep in bottle. Settling of powder may occur in the capsule, which is filled by weight not volume. Store in a cool, dry place after opening.

Seals/Symbols

GMP Quality Assured

Triangle K (Kosher)

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

See for yourself

Kava Kava Extract 250 mg by NOW label

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

Kava Kava Extract 250 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 250 mg by NOW

These are the 2 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 Veg. Capsule(s) Dosage formCapsule Servings per container60 Amounts shown are per serving.

Most supplement products combine several ingredients, and a medication can interact with the product through any one of them. Each ingredient below shows whether it has known drug interactions.

Eleuthero

Interacts with
1,140 drugs
100 mg per serving

Eleuthero is an herb traditionally used as an 'adaptogen' to fight fatigue, boost energy, and help the body handle stress. The scientific evidence beh...

Eleuthero monograph & interactions

Kava Kava Root Extract

Interacts with
1,166 drugs
250 mg per serving Form: 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 Root Extract monograph & interactions

Other (inactive) ingredients: Cellulose, Cellulose, Powder, Magnesium Stearate, Silica. These complete the product’s ingredient list but are not active constituents.

Interaction report

Kava Kava Extract 250 mg by NOW Drug Interactions

Want to check YOUR meds against Kava Kava Extract 250 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
1,348Drugs
248 Major 807 Moderate 293 Minor

Ingredients driving the most interactions

Kava Kava Root Extract 1,166
Eleuthero 1,140

Individual Drug Interactions

The ingredients in Kava Kava Extract 250 mg interact with 1,348 drugs. Click any drug to see the details.

2 of the 2 ingredients in Kava Kava Extract 250 mg interact with drugs. Each result below shows which ingredient is responsible. Kava Kava Root Extract Eleuthero

Each ingredient & the kinds of drugs it affects

For each ingredient in Kava Kava Extract 250 mg with known interactions, here are the types of medications they can affect. Open any type for the detail — or search your exact drug in the checker above.

Kava Kava Root 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 Root Extract full monograph & interactions

Eleuthero10 drug types · 1,140 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, eleuthero may have antiplatelet effects and may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
In vitro and animal research shows that a constituent of eleuthero, dihydroxybenzoic acid, appears to inhibit platelet aggregation. Concomitant use with anticoagulant or antiplatelet drugs might increase the risk of bleeding. This effect has not been reported in humans.

Likelihood Possible Evidence D
Antidiabetes Drugs

Theoretically, eleuthero might have additive effects when used with antidiabetes drugs.
Animal research suggests that certain constituents of eleuthero have hypoglycemic activity in both healthy and diabetic animals. A small study in adults with type 2 diabetes also shows that taking eleuthero for 3 months can lower blood glucose levels. However, one very small study in healthy individuals shows that taking powdered eleuthero 3 grams, 40 minutes prior to a 75-gram oral glucose tolerance test, significantly increases postprandial blood glucose levels when compared with placebo. These contradictory findings might be due to patient-specific variability and variability in active ingredient ratios.

Likelihood Possible Evidence B
Cytochrome P450 1A2 (Cyp1A2) Substrates

Theoretically, eleuthero might increase levels of drugs metabolized by CYP1A2.
In vitro and animal research suggest that standardized extracts of eleuthero inhibit CYP1A2. This effect has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 2C9 (Cyp2C9) Substrates

Theoretically, eleuthero might increase levels of drugs metabolized by CYP2C9.
In vitro and animal research suggest that standardized extracts of eleuthero might inhibit CYP2C9. This effect has not been reported in humans.

Likelihood Possible Evidence D
Digoxin (Lanoxin)

Eleuthero might increase serum digoxin levels and increase the risk of side effects.
In one case report, a 74-year-old male who was stabilized on digoxin presented with an elevated serum digoxin level after starting an eleuthero supplement, without symptoms of toxicity. After stopping the supplement, serum digoxin levels returned to normal. It is not clear whether this was due to a pharmacokinetic interaction or to interference with the digoxin assay. Although the product was found to be free of digoxin and digitoxin, it was not tested for other contaminants.

Likelihood Unlikely Evidence D
Immunosuppressants

Theoretically, eleuthero might interfere with immunosuppressive drugs because of its immunostimulant activity.
Animal and in vitro research shows that eleuthero extracts have immunomodulatory effects, including increasing cellular and humoral activity.

Likelihood Possible Evidence D
P-Glycoprotein Substrates

Theoretically, eleuthero might increase levels of P-glycoprotein substrates.
In vitro research suggests that eleuthero can inhibit the multi-drug transporter protein, P-glycoprotein. However, it is too soon to tell if this is clinically important. This interaction has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 2D6 (Cyp2D6) Substrates

Theoretically, eleuthero might increase levels of drugs metabolized by CYP2D6.
In vitro and animal research suggest that standardized extracts of eleuthero might inhibit CYP2D6. However, research in healthy human volunteers has found that taking eleuthero 485 mg twice daily for 14 days does not inhibit CYP2D6 drug metabolism.

Likelihood Unlikely Evidence B
Cytochrome P450 3A4 (Cyp3A4) Substrates

Theoretically, eleuthero might increase levels of drugs metabolized by CYP3A4.
In vitro and animal research suggest that standardized extracts of eleuthero might inhibit CYP3A4. However, research in healthy human volunteers has found that taking eleuthero 485 mg twice daily for 14 days does not inhibit CYP3A4 drug metabolism.

Likelihood Unlikely Evidence B
Organic Anion-Transporting Polypeptide Substrates (Oatp)

Theoretically, eleuthero might decrease levels of drugs metabolized by OATP.
In vitro research suggests that eleuthero inhibits OATP2B1, which might reduce the bioavailability of oral drugs that are substrates of OATP2B1. Due to the weak inhibitory effect identified in this study, this interaction is not likely to be clinically significant.

Likelihood Possible Evidence D
Eleuthero full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Kava Kava Extract 250 mg, from the product label.

NOW

See all NOW products
Name
NOW FOODS
Street Address
395 S. Glen Ellyn Rd.
City
Bloomingdale
State
IL
ZipCode
60108
Web Address
nowfoods.com
Pharmacist Counseling Corner

Kava Kava Extract 250 mg by NOW: Common Questions

Does Kava Kava Extract 250 mg by NOW interact with any medications?
Yes. Based on its ingredients, Kava Kava Extract 250 mg has a known interaction with 1,348 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 250 mg contains 2 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is 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.
Is this safe to take long-term?
Not well studied. Eleuthero's long-term safety evidence is limited, and kava has been tied to liver damage, especially with prolonged use — some cases showed up after just 3–4 weeks. Keep use short-term and talk with your pharmacist or doctor before going longer.
Can I take this if I'm pregnant or breastfeeding?
No. Both eleuthero and kava lack enough safety data, so they're best avoided during pregnancy. Kava is also not safe while breastfeeding. Talk with your doctor or pharmacist about safer alternatives.
What are the most common side effects?
Eleuthero can cause diarrhea, nausea, headache, and stomach upset; nervousness and anxiety show up in some people too. Kava commonly causes drowsiness, dizziness, headache, and memory problems. Both can affect blood pressure and mood.
Will this help my anxiety or sleep?
The evidence is weak. Kava is rated possibly ineffective for anxiety, and for sleep the proof isn't strong enough to rate. Eleuthero hasn't been studied for either. Don't count on this product to treat either condition without talking to your doctor first.
Should I be worried about liver damage?
Kava has been linked to over 100 cases of liver injury worldwide. Most happened with heavy, prolonged use, but some appeared in just weeks. If you drink heavily, take other liver-stressing drugs, or have liver disease, this product is not for you — check with your pharmacist.

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

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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 250 mg label
Go deeper

The Full Monographs Behind Kava Kava Extract 250 mg’s Ingredients

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

Herb & supplement monograph

Eleuthero

Interacts with 1,140 drugs

Eleuthero is an herb traditionally used as an 'adaptogen' to fight fatigue, boost energy, and help the body handle stress. The scientific evidence behind these uses is limited and mixed, so...

Read the full Eleuthero monograph → 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 250 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 95 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.

Eleuthero 24 references
  1. McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.
  2. McRae S. Elevated serum digoxin levels in a patient taking digoxin and Siberian ginseng. CMAJ 1996;155:293-5.
  3. Awang DVC. Siberian ginseng toxicity may be case of mistaken identity (letter). CMAJ 1996;155:1237.
  4. Mills S, Bone K. Principles and Practice of Phytotherapy. London: Churchill Livingstone, 2000.
  5. Harkey MR, Henderson GL, Zhou L, et al. Effects of Siberian ginseng (Eleutherococcus senticosus) on c-DNA-expressed P450 drug metabolizing enzymes. Alt Ther 2001;7:S14.
  6. Hikino H, Takahashi M, Otake K, Konno C. Isolation and hypoglycemic activity of eleutherans A, B, C, D, E, F, and G: glycans of Eleutherococcus senticosus roots. J Nat Prod 1986;49:293-7. PubMed
  7. Yun-Choi HS, Kim JH, Lee JR. Potential inhibitors of platelet aggregation from plant sources, III. J Nat Prod 1987;50:1059-64. PubMed
  8. Donovan JL, DeVane CL, Chavin KD, et al. Siberian Ginseng (Eleutheroccus senticosus) Effects on CYP2D6 and CYP3A4 Activity in Normal Volunteers. Drug Metab Dispos 2003;31:519-22.. PubMed
  9. Hartz AJ, Bentler S, Noyes R et al. Randomized controlled trial of Siberian ginseng for chronic fatigue. Psychol Med 2004;34:51-61. PubMed
  10. Sievenpiper JL, Arnason JT, Leiter LA, Vuksan V. Decreasing, null and increasing effects of eight popular types of ginseng on acute postprandial glycemic indices in healthy humans: the role of ginsenosides. J Am Coll Nutr 2004;23:248-58. PubMed
  11. Dasgupta A, Wu S, Actor J, et al. Effect of Asian and Siberian ginseng on serum digoxin measurement by five digoxin immunoassays. Significant variation in digoxin-like immunoreactivity among commercial ginsengs. Am J Clin Pathol 2003;119:298-303. DOI
  12. Takahashi T, Kaku T, Sato T, et al. Effects of Acanthopanax senticosus HARMS extract on drug transport in human intestinal cell line Caco-2. J Nat Med. 2010;64(1):55-62. PubMed
  13. Fuchikami H, Satoh H, Tsujimoto M, Ohdo S, Ohtani H, Sawada Y. Effects of herbal extracts on the function of human organic anion-transporting polypeptide OATP-B. Drug Metab Dispos 2006;34:577-82. PubMed
  14. Friedman, J. A., Taylor, S. A., McDermott, W., and Alikhani, P. Multifocal and recurrent subarachnoid hemorrhage due to an herbal supplement containing natural coumarins. Neurocrit.Care 2007;7(1):76-80. PubMed
  15. Molokovskii, D. S., Davydov, V. V., and Tiulenev, V. V. [The action of adaptogenic plant preparations in experimental alloxan diabetes]. Probl.Endokrinol.(Mosk) 1989;35(6):82-87.
  16. Schmolz, M. W., Sacher, F., and Aicher, B. The synthesis of Rantes, G-CSF, IL-4, IL-5, IL-6, IL-12 and IL-13 in human whole-blood cultures is modulated by an extract from Eleutherococcus senticosus L. roots. Phytother.Res 2001;15(3):268-270.
  17. Huang, D. B., Ran, R. Z., and Yu, Z. F. [Effect of Acanthopanax senticosus injection on the activities of human tumor necrosis factor and natural killer cell in blood in the patients with lung cancer]. Zhongguo Zhong.Yao Za Zhi. 2005;30(8):621-624.
  18. Niu, H. S., Hsu, F. L., Liu, I. M., and Cheng, J. T. Increase of beta-endorphin secretion by syringin, an active principle of Eleutherococcus senticosus, to produce antihyperglycemic action in type 1-like diabetic rats. Horm.Metab Res 2007;39(12):894-898
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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.

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