Department of Psychiatry, Yale School of Medicine, New Haven, CT, United States of America; Psychiatry Service, Veterans Affairs Connecticut Healthcare System, West Haven, CT, United States of America.
2 papers in the library · 112 citations · publishing 2022-2024
In an exploratory randomized, double-blind, placebo-controlled trial, a pulse regimen of three doses of psilocybin (0.143 mg/kg) given about five days apart did not significantly reduce cluster headache attack frequency compared to placebo. Over three weeks, attack frequency changed by −3.2 attacks per week with psilocybin (baseline 9.6) and 0.03 attacks per week with placebo (baseline 8.9), a difference that was not statistically significant. The overall effect size was moderate (d = 0.69), but large in chronic participants (d = 1.25) and small in episodic participants (d = 0.35). Changes in attack frequency were not linked to the intensity of acute psychedelic effects. Psilocybin was well-tolerated with no serious adverse events.
In a blinded extension of a prior randomized trial, ten people with cluster headache received a second round of three doses of psilocybin (10 mg/70 kg, five days apart) at least six months after their first round. Attack frequency dropped significantly from a baseline of 18.4 attacks per week to 9.8 attacks per week in the three weeks after the first dose, a reduction of about 50%. This benefit occurred regardless of whether the participant had responded to psilocybin in the first round. No serious or unexpected adverse events occurred. The findings suggest that repeating a pulse of psilocybin can substantially reduce cluster headache attacks and that prior response does not predict the effect of retreatment.