Kava for Insomnia
Verdict: Taiwan Regulatory Restriction
Across 3 PubMed studies, the evidence for Kava in Insomnia grades Tier D — counter-evidence.
D 🔴 D Counter-Evidence Taiwan Regulatory Restriction
Why this grade7-layer evidence engine
⚖️
Scoring transparency
All scores computed by a 7-layer evidence engine — fully auditableRaw score 0.29
D
C
B
A
S
← counter-evidence / ineffectiveeffective / strong evidence →
Final grade
D · Taiwan Regulatory Restriction
Confidence
76%
Broadly consistent
Evidence level
E6
Multiple smaller RCTs (n<500)
▸View the full decision path (audit trail)
- compute_raw_score — 加權公式: L2×0.30 + L3×0.25 + L5×0.25 + L11×0.10 + L1×0.10 = 0.294
- tier_from_score — 依分數區間映射至 tier letter
- apply_hec_rules — 無高階證據可裁決
- tier_strict_requirement_check — D 級條件未達 (需 E1-E3 negative；實際 E6)
- detect_disputes — 偵測到 0 個 hard + 0 個 soft dispute
- decide_status — 依 tier + dispute 結果決定 status
PubMed studies (3)L2 · primary research & systematic reviews
An internet-based randomized, placebo-controlled trial of kava and valerian for anxiety and insomnia
Finding: Neither kava nor valerian relieved insomnia more than placebo; valerian vs placebo difference 0.4 points (95% CI -1.3 to +2.1), not significant.
View on PubMed Clinical efficacy of kava extract WS 1490 in sleep disturbances associated with anxiety disorders (multicenter RCT)
Finding: Significant improvement in sleep quality (P=0.007) and recuperation (P=0.018) vs placebo, but population had anxiety-associated sleep disturbance — sleep effect confounded by anxiolysis, not standalone primary insomnia.
View on PubMed Kava and valerian in the treatment of stress-induced insomnia
Finding: Small uncontrolled pilot reporting reduced stress-related insomnia with kava, but no placebo arm and sleep benefit tied to stress reduction; not standalone primary-insomnia evidence.
View on PubMed Regulatory & authoritative positionsL4/L5 · FDA / EMA / NIH ODS / Cochrane / Mayo …
L4a US FDA
Cautious
Kava-containing products have been associated with liver-related injuries — including hepatitis, cirrhosis, and liver failure — in over 25 reports of adverse events in other countries. source↗
L4b EU EFSA
Against
The Medicines for Human Use (Kava-kava) (Prohibition) Order 2002... prohibits the sale, supply or importation of any medicinal product consisting of or containing Kava-kava. Following reports associating kava with cases of severe hepatotoxicity, Germany's BfArM revoked the marketing authorisations for kava-containing medicinal products in 2002. source↗
L4c UK NHS
Against
Subject to the provisions of this Order, no person shall sell, supply or import for the purpose of sale or supply any medicinal product that consists of or contains Kava-kava... 'Kava-kava' means any plant belonging to the species Piper methysticum. source↗
L4d TW TFDA / 衛福部
Against
台灣亦將卡瓦胡椒列為禁用之中藥成分(衛署中字)；卡瓦胡椒因具有潛在的嚴重肝毒性風險，目前在德國、瑞士、加拿大、英國等多國曾受到限制或禁止販售；美國 FDA 於 2002 年已發出消費者警告。 source↗
L4e WHO
Cautious
Assessment of the risk of hepatotoxicity with kava products. [WHO, 2007] The objective of this assessment was to examine the safety of kava with a focus on the issue of hepatotoxicity, in view of reports of severe liver injury, including cases of liver failure requiring transplantation, associated with the consumption of kava-containing products. source↗
L5a NIH Office of Dietary Supplements
Cautious
Kava supplements may be helpful for anxiety, but they may need to be taken for several weeks to produce an effect. ... Various kava products have been linked to rare cases of liver injury, some of which have been serious or even fatal. source↗
L5b Mayo Clinic
Cautious
Kava has been linked to liver damage, including hepatitis and liver failure that in some cases required a liver transplant or led to death. Because of this risk, kava is not recommended. If you have liver problems or take medications that affect your liver, talk to your doctor before using kava. source↗
L5c Cleveland Clinic
Cautious
Kava may help with anxiety, but it comes with a serious caveat: It's been linked to liver damage. Because of that risk, it's not something we recommend reaching for, and you should talk to your doctor before taking it — especially if you have liver issues or take other medications. source↗
L5e Specialty Society (condition-mapped)
Against
The AASM 2017 Clinical Practice Guideline for the pharmacologic treatment of chronic insomnia in adults (Sateia et al.) evaluates specific agents (e.g., suvorexant, eszopiclone, zolpidem, doxepin, ramelteon) and notes 'we suggest that clinicians not use trazodone, tiagabine, diphenhydramine, melatonin, tryptophan, and valerian.' Kava is not among the agents the AASM recommends for chronic insom… source↗