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.
- Ketamine triples the odds of remaining abstinent during the first month post-treatment, but the effect loses statistical significance between month one and month six.
- Adverse effects were mild: transient increases in blood pressure and dissociative sensations that subside within half an hour, with no differences in study dropout rates.
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: the effect is real in the short term, but science cannot yet say whether it holds up beyond a few weeks.
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, always as an adjunct to psychotherapeutic treatment and not as a standalone substance.
The numbers
In the first month following the intervention, those who received ketamine were nearly three times more likely to remain abstinent than the control group (odds ratio of 3.27). 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. Regarding safety, there were no relevant differences in treatment dropouts or serious adverse effects between groups: the most frequent occurrences were 20% to 30% increases in diastolic and systolic blood pressure, along with dissociative sensations that disappeared in less than half an hour.
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 supports a real but modest and short-lived effect, not a cure, 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.
