Psilocybin could be six times better at helping people abstain from smoking tobacco after six months than nicotine patches, according to the results of a recently published study conducted at Johns Hopkins University and the University of Alabama at Birmingham.
The psychedelic drug, psilocybin, found in numerous species of mushrooms around the world, has long been investigated for its addiction-fighting qualities, leading researchers to conduct a pilot study to discover how effective it is at helping people abstain from smoking for a prolonged period of time when compared to nicotine patches, a standard smoking cessation treatment.
Published in the journal JAMA Network Open, the study recruited a cohort of 82 participants. During the study, nearly half of the participants, 42, had their tobacco addiction treated with a single dose of psilocybin, and the remaining 40 were administered nicotine patches.
The cohort had a mean age of 47.6, smoked an average of 15.7 cigarettes a day, and had a median of six previous cessation attempts. 53 participants had prior experience with psychedelics.
Participants were randomly assigned to either the psilocybin or nicotine patch group. The study was not double-blind, meaning both researchers and participants in the psilocybin group knew they would receive a high dose of the drug, and there was no placebo.
The cohort was monitored for six months, with all participants receiving a standardised 13-week-long cognitive behavioural therapy course.
The psilocybin group were administered a single, high dose, 30 mg/70 kg, of psilocybin at the beginning of the study, and the nicotine group following an 8 to 10 week course of US Food and Drug Administration–approved nicotine patch treatment.
To enable researchers to be confident in the results, they used self-reported admissions of smoking abstinence in combination with biochemical verification methods, which measure biomarkers present in the body that indicate if a participant had smoked.
No serious adverse events (AEs) were reported. However, 80 AEs were reported for less-serious complaints and observations such as ‘modest elevations in blood pressure and heart rate’ in the psilocybin group participants.
At the end of the six-month study period, only 4 (10%) of the nicotine patch group participants had abstained entirely from smoking, while 17 (41%) of the psilocybin group participants had stopped.
Participants in the psilocybin group who returned to smoking within the six-month study period smoked a mean of 50% fewer cigerettes per day than participants in the nicotine patch group who returned to smoking in the same period.
Researchers used a technique called logistic regression to project that those in the psilocybin group had more than six times the odds of reaching six months without smoking than those in the nicotine patch group.
This study found a single, high dose of psilocybin to be a safe and effective treatment for the cessation of cigerettes, with a higher rate of success than nicotine patch treatment. Researchers highlighted psilocybin’s anti-addiction qualities and the mechanisms that it uses to combat nicotine addiction.
Lead author Matthew Johnson from Johns Hopkins University said he was surprised by the magnitude of the effect. “A single psilocybin dose combined with manualized CBT yielded significantly greater smoking abstinence than the nicotine patch paired with the same CBT. At 6 months, the psilocybin group had more than 6 times greater odds of showing prolonged abstinence (primary outcome) and more than 3 times greater odds of showing 7-day point prevalence abstinence (secondary outcome). Participants in the psilocybin group smoked a mean of approximately 50% fewer CPD between the target quit date and 6-month follow-up,” Johnson told NPR.
“The results of this study add to the increasing evidence that psychedelic treatment may have general antiaddiction efficacy across various addictive drugs. Psilocybin’s lack of direct interaction with nicotinic acetylcholine receptors (or receptors mediating the effects of other addictive drugs) highlights psychedelic therapy as a unique approach wherein the pharmacotherapy does not directly alter drug reinforcement or withdrawal but may instead act via higher-order psychological systems, such as changes in self-concept and enhanced psychological flexibility.”
The study has several limitations. Because it was not double-blinded, participant expectations could have influenced outcomes. The researchers noted, however, that maintaining proper blinding has been an ongoing challenge in psychedelic research due to the drug’s obvious mind-altering effects.
Additionally, 65% of participants had previous experience with psychedelics – far higher than the 13.8% national average – suggesting the sample may not be representative of the general population. The participants were also highly educated with above-average intelligence, which could affect the generalisability of the results.
Smoking remains the leading cause of preventable death in the US, claiming approximately 480,000 lives annually. Existing treatments, including nicotine replacement therapy, varenicline and bupropion, typically show modest long-term success rates of 20% to 30%.