“They clearly found a dose effect and clinically meaningful improvement in just three weeks,” said Dr. Matthew Johnson, a professor in psychedelics and consciousness at Johns Hopkins Medicine in Baltimore.“Participants were requested to remain off antidepressant treatment during the first 3 weeks after the trial-drug administration; however, these medications could be started at any time during the trial if deemed clinically necessary by a physician investigator,” the study said.“This does not appear to be acknowledged in the paper.” Safety profile Headache, nausea, fatigue and dizziness plagued 77% of the study participants and occurred at all dosage levels, which experts say is a typical response on the day of psilocybin administration.A small number of people in all three dosage groups experienced suicidal thoughts or injured themselves over the 12-week follow-up period, the study found.Within the first three weeks alone, two people in the 25-milligram group thought about suicide and two intentionally injured themselves."