Psilocybin Produces Long-Term Antidepressive Benefits

By Jonathan Springston, Editor, Relias Media

Adults with depressive disorder who received psilocybin (a psychedelic compound found in many fungi species) in combination with psychotherapy experienced “substantial” relief from their symptoms, as long as one year for some patients, according to the results of a recently published paper.

The authors recruited 27 patients age 21 to 75 years with moderate to severe unipolar depression (67% women, 92% white, one Black participant, one Asian participant). Patients had to experience symptoms for about two years before enrollment. All participants were randomized to an immediate or delayed (i.e., after a waiting period of eight weeks) treatment of psilocybin (two doses) and supportive psychotherapy. A total of 24 patients completed the full treatment and were followed at intervals up to 12 months after taking their second psilocybin dose.

Investigators measured symptoms using the GRID-Hamilton Depression Rating Scale. A score of 24 or more indicates severe depression, 17-23 moderate depression, 8-16 mild depression, and 7 or lower no depression. At enrollment, these patients scored 17 or higher on the scale. Participants checked in after one week, at four weeks, at three months, at six months, and one last time at 12 months after treatment. From a mean score of 22.8 before treatment, the mean score had fallen to 7.7 at 12 months.

There were no adverse events, no one experienced worse depressive symptoms while on this therapy, and no one reported using psilocybin or other psychedelic drugs during follow-up. Eight patients started a new course of standard antidepressant drug therapy at some time during the follow-up, although the researchers noted the depression rating scale scores for these patients at baseline were high.

In addition to the limits of the small population size and the homogenous makeup of the cohort, the authors suggested future research should include a comparison group that could allow for even longer-term follow-up.

“Although evidence to date suggests that psilocybin has relatively low abuse potential, there remains concern for its potential to cause harm or encourage substance misuse in vulnerable populations. The present study highlights a key potential advantage of psilocybin treatment over ketamine in that antidepressant effects after just two administrations of psilocybin paired with psychological support appear to be sustained through 12 months, which is well beyond the duration of effects reported with ketamine,” the authors concluded. “It will be important for future research to determine the risks and benefits of additional psilocybin administration for those who failed to respond or experienced early relapse.”

Psilocybin research is not anything new, although perhaps not totally mainstream yet (ethical views are evolving). In addition to depression relief, it seems psilocybin (as well as cannabis) could be used to treat various medical disorders. In December, the NIH awarded a funding grant to a group of investigators to study how psilocybin could help patients quit smoking. This was the first NIH grant awarded for this type of research in 50 years.

For more on this and related subjects, be sure to read the latest issues of Integrative Medicine Alert and Neurology Alert.