Participants who got single dose of psilocybin were more likely to abstain from cocaine than those who got placebo Results from a new clinical trial show that a single dose of psilocybin could be an effective treatment for cocaine addiction. The study, published in Jama Network Open this month, showed that 19 participants who received a single dose of psilocybin were more likely to abstain from cocaine than 17 participants who received a placebo of diphenhydramine, a common antihistamine. Contin