2021-09-07-世界卫生组织-Kratom,_mitragynine,_7-hydroxymitragynine_pre-review_report_65页_912kb

Summary

Substance Overview
Kratom (Mitragyna speciosa) is a Southeast Asian tree traditionally used for medicinal and recreational purposes, containing psychoactive alkaloids mitragynine (major component, up to 66% of alkaloids) and 7-hydroxymitragynine (less than 1%, but often concentrated in products). It acts as a partial agonist at mu-opioid receptors, exhibiting opioid-like effects at higher doses and stimulant-like effects at lower doses.

Pharmacology & Toxicity

• Pharmacokinetics: Oral bioavailability varies widely by species. In humans, mitragynine and 7-hydroxymitragynine have limited pharmacokinetic data. Animal and human studies suggest interactions with cytochrome P450 enzymes.
• Toxicity: Acute toxicity includes respiratory depression, seizures, and liver damage. Chronic use may lead to dependence, withdrawal symptoms, and neuropsychiatric issues. Overdose risk is high when mixed with other substances.

Public Health Concerns

• Kratom misuse is increasing globally, particularly in the US and Western Europe.
• Attributing deaths solely to kratom is challenging due to poly-substance use.
• Reports of liver toxicity and severe neuropsychiatric effects are concerning, though not universal in long-term users.

Regulatory Status
Uncontrolled at the international level but scheduled or restricted in many countries (e.g., US, Canada). ASEAN banned kratom in herbal supplements but allows cultivation.

Scientific Matters for Scheduling
No approved medical uses. Evidence suggests potential therapeutic applications (e.g., analgesia, addiction treatment), but lacks human clinical trial data. Potential for dependence and adverse effects noted.

Recommendations for ECDD
Consider scheduling if evidence of abuse potential outweighs benefits, given the limited medical data but significant public health burden.