In brief
- A team from West China Hospital (Sichuan University) has published the first meta-analysis focused solely on ketamine for substance use disorders: 15 trials, 798 participants.
- The abstinence odds estimate favoured ketamine before one month (OR 3.27); an odds ratio does not mean tripling probability. The one-to-six-month result was uncertain.
- Adverse-event and dropout evidence was of very low certainty; not observing significant differences does not establish safety.
A meta-analysis published in Frontiers in Psychiatry gathers, for the first time, all available evidence on ketamine as an aid for quitting alcohol, cocaine, heroin, or tobacco. The conclusion is nuanced: there is an early signal, but its duration and safety balance remain uncertain.
What they analyzed
The team, led by Shu-Ping Fang and Mao-Sheng Ran, screened 15 randomized trials involving 798 people (466 in the ketamine group). Four studies addressed alcohol, three cocaine, two heroin, two other opioids, and one tobacco; in three of the fifteen, there was also associated depression. Most administered the substance intravenously (twelve trials) and the rest intramuscularly, with doses between 0.20 and 2.0 mg/kg, with protocols using ketamine with or without structured psychotherapy.
The numbers
Before one month, the pooled estimate was OR 3.27 (95% CI 1.55–6.92). This compares odds, not a direct multiplication of probabilities. Between month one and month six, the effect remained favorable but no longer reached statistical significance (1.74). Cravings did not decrease significantly in the first month, although they did show a moderate reduction later on. No significant between-group differences in dropout or adverse events were found, but certainty was very low. The article describes transient blood-pressure increases and dissociation in individual trials, not their pooled prevalence or established general safety.
What it implies
The authors themselves classify the certainty of the evidence as moderate for the first month and low or very low for the remaining results, and only seven of the fifteen trials provided abstinence data usable for statistical calculation. They also acknowledge a common limitation in this type of ketamine study: because its dissociative effects are difficult to mask, participants and therapists often intuit who is receiving the actual substance, which can inflate the perceived result. None of the trials were conducted outside of a controlled clinical environment, so these data say nothing about unsupervised use. For those who already use ketamine or are considering treatment with it within a harm reduction program, the useful takeaway is this: the evidence suggests a possible early benefit without establishing its duration or confirming safety, and cardiovascular monitoring during infusion remains the most solid practical precaution provided by the study. It aligns with what we saw when comparing intravenous ketamine with esketamine for depression: the effect exists, but its duration is the great unknown.
Source
- Fang SP, Yang X, Zhao DC, et al. Ketamine for substance use disorders: a systematic review and meta-analysis. Frontiers in Psychiatry, July 17, 2026.
Educational content written from a harm reduction perspective and with respect for individual freedom. It is not a substitute for advice from a healthcare professional and is not intended to encourage or condemn any drug use.
