Enduring changes in personality/attitudes , depression , spirituality , anxiety , wellbeing , substance misuse , meditative practice s , and mindfulness were documented .
Mystical experiences , connectedness , emotional breakthrough , and increased neural entropy were related to these long-term changes in psychological functioning .
Finally , with proper screening , preparation , supervision , and integration , limited aversive side effects were noted by study participants .
Research into the basic effects and therapeutic applications of  psychedelic drugs  has grown considerably in recent years .
Yet , pressing questions remain regarding the substances ' lasting effects .
Although individual studies have begun monitoring sustained changes , no study to- date has synthesized this information .
Safety, tolerability, and efficacy of psilocybin in 9 patients with obsessive-compulsive disorder.
BACKGROUND Anecdotal reports suggest that psychedelic agents may relieve symptoms of  obsessive-compulsive disorder ( OCD ) . This modified double-blind study investigated the safety , tolerability , and clinical effects of psilocybin , a potent 5-HT(1A ) and 5-HT(2A/2C ) agonist , in patients with OCD . METHOD Nine subjects with DSM-IV-defined OCD and no other current major psychiatric disorder participated in up to 4 single-dose exposures to psilocybin in doses ranging from sub-hallucinogenic to frankly hallucinogenic . Low ( 100 microg/kg ) , medium ( 200 microg/kg ) , and high ( 300 microg/kg ) doses were assigned in that order , and a very low dose ( 25 microg/kg ) was inserted r and omly and in double-blind fashion at any time after the first dose . Testing days were separated by at least 1 week . Each session was conducted over an 8-hour period in a controlled environment in an outpatient clinic ; subjects were then transferred to a psychiatric inpatient unit for overnight observation . The Yale-Brown Obsessive Compulsive Scale ( YBOCS ) and a visual analog scale measuring overall obsessive-compulsive symptom severity were administered at 0 , 4 , 8 , and 24 hours post-ingestion . The Hallucinogen Rating Scale was administered at 8 hours , and vital signs were recorded at 0 , 1 , 4 , 8 , and 24 hours after ingestion . The study was conducted from November 2001 to November 2004 . RESULTS Nine subjects were administered a total of 29 psilocybin doses . One subject experienced transient hypertension without relation to anxiety or somatic symptoms , but no other significant adverse effects were observed . Marked decreases in OCD symptoms of variable degrees were observed in all subjects during 1 or more of the testing sessions ( 23%-100 % decrease in YBOCS score ) . Repeated- measures analysis of variance for all YBOCS values revealed a significant main effect of time on Wilks lambda ( F = 9.86 , df = 3,3 ; p = .046 ) , but no significant effect of dose ( F = 2.25 , df = 3,3 ; p = .261 ) or interaction of time and dose ( F = 0.923 , df = 9,45 ; p = .515 ) . Improvement generally lasted past the 24-hour timepoint . CONCLUSIONS In a controlled clinical environment , psilocybin was safely used in subjects with OCD and was associated with acute reductions in core  OCD symptoms in several subjects
Enduring changes in personality/attitudes , depression , spirituality , anxiety , wellbeing , substance misuse , meditative practice s , and mindfulness were documented .
Mystical experiences , connectedness , emotional breakthrough , and increased neural entropy were related to these long-term changes in psychological functioning .
Finally , with proper screening , preparation , supervision , and integration , limited aversive side effects were noted by study participants .
Research into the basic effects and therapeutic applications of  psychedelic drugs  has grown considerably in recent years .
Yet , pressing questions remain regarding the substances ' lasting effects .
Although individual studies have begun monitoring sustained changes , no study to- date has synthesized this information .