Table 2.

Modern day clinical interventional studies of classic and non-classic psychedelics in addiction.

Author	Diagnosis	Trial and treatment	N	Outcome
(56)	Alcohol dependence (DSM-IV)	Open-label single arm proof of concept 2× high doses of Psilocybin (0.3 mg/kg and 0.4 mg/kg) + 7× sessions of motivational enhancement therapy 3× preparation sessions, 2× integration sessions	10	Psilocybin rapidly and significantly reduced the percentage of drinking days and the number of heavy drinking days in this proof-of-concept study, with effects lasting up to 36 weeks post intervention. In secondary analyses psilocybin significantly reduced craving scores (50% reduction at 36 weeks follow up). Correlations between the acute effects of psilocybin predicted changes in drinking, craving and self-efficacy.
(57)	Nicotine addiction (minimum 10 cigarettes a day multiple unsuccessful past quit attempts, and still desire to quit smoking)	Open-label single arm proof of concept 2-3× administrations of psilocybin (20 mg/70 kg – moderate & 30 mg/70 kg – high). 15-week smoking cessation treatment protocol	15	Biomarkers assessing smoking status, and self-report measures of smoking behavior, demonstrated that 12 of 15 participants (80%) showed seven-day point prevalence abstinence at 6-month follow-up. 11/12 of these individuals reported cessation after just the first psilocybin administration.
(68)	Alcohol use disorder (DSM-5 moderate to severe AUD or DSM-IV alcohol dependence)	Double-blind placebo-controlled Phase IIa 3× 0.8 mg/kg intravenous ketamine infusion or saline infusion plus Psychological or Alcohol education	96	Significantly greater number of days abstinent from alcohol in the ketamine group compared with placebo group at 6-month follow-up (mean difference = 10.1, 95% CI = 1.1, 19.0), with the greatest reduction in the ketamine plus therapy group compared with the saline plus education group (15.9, 95% CI = 3.8, 28.1). There was no significant difference in relapse rate between the ketamine and placebo groups.
(58)	Alcohol use disorder (DSM-5)	Open-label single arm proof of concept 2× 187.5 mg MDMA-assisted psychotherapy sessions community based alcohol detox, 8x week recovery-based therapy	14	MDMA treatment was well tolerated by all participants. No unexpected adverse events were observed and psychosocial functioning improved across the cohort. At 9 months post detox, the average units of alcohol consumption by participants were 18.7 units per week compared to 130.6 units per week before the detox. This results compare favorably to outcomes from patients undergoing similar community based alcohol detox
(59)	Alcohol use disorder (DSM-5)	Double-blind randomized clinical trial, participants were offered 12 weeks of manualised psychotherapy and randomly assigned to receive psilocybin (25–40 mg/70 kg) vs. diphenhydramine (50–100 mg) during 2 day-long medication sessions at weeks 4 and 8. Outcomes assessed over a 32-week double-blind period following. Study medications were psilocybin, 25 mg/70 kg, vs. diphenhydramine, 50 mg (first session) Psychotherapy included motivational enhancement therapy and cognitive behavioral therapy.	93	Percentage of heavy drinking days during the 32-week double-blind period was 9.7% for the psilocybin group and 23.6% for the diphenhydramine group, a mean difference of 13.9%; (95% CI, 3.0–24.7; F1,86 = 6.43; p = 0.01). Mean daily alcohol consumption (number of standard drinks per day) was also lower in the psilocybin group. No serious adverse events among participants who received psilocybin.