CHAMGAP
APPROVEDReviewed and approved by the Chamgap Editorial Team (2026-07-11). The draft was written by AI, the existence of all 3 cited sources was verified at the original page, and the verdict passed blind grading and adversarial audit. Methodology v0.6.
Verdict No. 251 · Search date 2026-07-11 · Methodology v0.6

L-ornithine,
does it really help with Hangover and liver-fatigue improvement?

30-Second Summary
C
Evidence Grade C · 49 · Safety acceptable
There is a limited signal for post-hangover fatigue, but it is not evidence of improved liver function
What the
research shows
L-ornithine has a small crossover trial reporting improvement in next-morning fatigue and some mood measures after drinking, and trials of general fatigue and stress also improved selected subjective measures. However, the hangover experiment included only 11 participants, the acute alcohol-metabolism experiment only 16, and the research is concentrated in one corporate network and Japanese populations, so the rating is C. Improvement in liver function or liver disease has not been established for L-ornithine alone.
What the
ads claim
Advertisements use the urea cycle and ammonia metabolism to present 'liver fatigue recovery,' 'hangover removal,' and 'alcohol breakdown' together. Human evidence mainly concerns subjective fatigue, mood, and sleep scales, not accelerated alcohol elimination or improved liver function.
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Useful facts when choosing a product

  • The hangover crossover trial used 400 mg after drinking and analyzed 11 participants.
  • Doses in general-fatigue trials ranged from 400 mg/day to a short-term dose of 6,000 mg/day.
  • L-ornithine alone is not the same formulation as L-ornithine-L-aspartate used in hepatic encephalopathy.
  • Human trials primarily measured fatigue, mood, sleep questionnaires, and cortisol rather than clinical liver outcomes.
Gap Measurement · Verdict 251 · C 49
What advertising claims
What independent, higher-quality research supports
△ GAP
01

What the research actually shows

The Kokubo 2013 crossover trial found that 400 mg ornithine after drinking reduced next-morning fatigue, lassitude, and selected mood scores in 11 adults with the alcohol-flusher phenotype, but a separate experiment in 16 participants found no difference in breath alcohol or acute intoxication measures. The Sugino 2008 crossover trial in 17 participants reported improvement in selected measures of subjective post-exercise fatigue. The Moriyasu 2024 trial in 65 participants improved fatigue-inertia the morning after social stress but did not improve salivary cortisol. These studies did not test clinical liver disease or liver-enzyme improvement.

02

Why this is classified as C (49)

Because selected measures of post-hangover fatigue and general fatigue were repeatedly positive in small randomized trials, the evidence is not ungradable or D. The small studies, corporate links, population concentration, subjective endpoints, and absence of liver-function data limit the rating to C with 49 points.

Counterpoint. A signal remains for the narrow outcome of next-morning fatigue after drinking. This judgment does not include liver-enzyme improvement or treatment of liver disease.

Rejudgment record. Reassessment (cross-check reflected) — Small RCT signals for post-hangover and general fatigue, but corporate links, subjective endpoints, inadequate independent replication, and no evidence of improved liver function

Sub-claim grades by effect

This ingredient is marketed for several effects. A single overall grade blends strong and weak claims together, so each effect is graded separately here. The overall grade reflects the strongest disconfirming or core claim.

Effect (sub-claim)GradeBasis
Post-hangover fatigue and stressCSmall, industry-linked studies of subjective outcomes
Alcohol eliminationDA 16-person trial found no effect on breath alcohol or intoxication

Cross-check — Codex and Claude

This verdict was drafted by Codex through literature review and source-existence checks, cross-checked through blind grading and adversarial audit, and settled by reapplying the methodology boundary rules. Cases with split grades were resolved through rejudgment.
03

Evidence Table

StudyDesignSampleFundingEndpointResultWeight
Kokubo T et al. 2013Randomized double-masked placebo-controlled crossover trial16Kirin investigators and Kyowa productNext-morning fatigue, mood, salivary cortisol, and breath alcoholSelected next-morning subjective measures and cortisol improved, but acute alcohol metabolism did not differ from placebo.Key
Moriyasu K et al. 2024Randomized double-blind placebo-controlled parallel trial65Sponsored by Kirin with employee authorsFatigue, mood, and salivary cortisol after social stressNext-morning fatigue-inertia and anger-hostility improved, but cortisol did not differ.Supportive
Sugino T et al. 2008Double-blind placebo-controlled crossover trial17Research funding from Kyowa Hakko KogyoPost-exercise subjective fatigue, metabolism, and performanceSelected subjective fatigue and female-subgroup performance measures improved.Supportive
§

Receipt — 3 References

All 3 cited sources were verified for existence at the original page (as of 2026-07-11).

Kokubo T, Ikeshima E, Kirisako T, Miura Y, Horiuchi M, Tsuda A. 2013. A randomized, double-masked, placebo-controlled crossover trial on the effects of L-ornithine on salivary cortisol and feelings of fatigue of flushers the morning after alcohol consumption. Biopsychosoc Med. 7:6. PMID: 23414576. DOI: 10.1186/1751-0759-7-6.
checked
Moriyasu K, Nakajima A, Morita M. 2024. Effects of Oral Ingestion of L-Ornithine on Mental Stress and Fatigue Based on the Trier Social Stress Test in Healthy Humans: A Randomized, Double-Blind, Placebo-Controlled, Parallel-Group Trial. J Clin Med. 13(24):7583. PMID: 39768508. DOI: 10.3390/jcm13247583.
checked
Sugino T, Shirai T, Kajimoto Y, Kajimoto O. 2008. L-ornithine supplementation attenuates physical fatigue in healthy volunteers by modulating lipid and amino acid metabolism. Nutr Res. 28(11):738-743. PMID: 19083482. DOI: 10.1016/j.nutres.2008.08.008.
checked
Draft and rewrite: Codex (AI) · Verification: Codex blind grading and adversarial audit · Final adjudication: Claude
Reviewed and approved: Chamgap Editorial Team · Approval date: 2026-07-11 · Corrections: none

Cite this verdict

L-ornithine x hangover and liver-fatigue improvement Evidence Grade C card
[Chamgap] L-ornithine x hangover and liver-fatigue improvement — Evidence Grade C·49. 3 cited sources checked. Source: https://health-receipt.pages.dev/en/verdicts/liver/l-ornithine-hangover-liver-fatigue/ · CC BY 4.0

CC BY 4.0 — free to use with attribution; do not distort grades, numbers, or verdict meaning.

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What this document does and does not do

Chamgap is an information source. It reports what research has and has not confirmed; it does not tell readers what to take or buy. That decision belongs to readers and, when needed, medical or legal professionals. This verdict reflects literature available up to the search date and may change as new research appears. Nothing here is medical advice.