News release

From: Springer Nature

Medicine: Psychedelic can quickly reduce depressive symptoms

A single dose of the psychedelic drug dimethyltryptamine (DMT), given with psychological support, rapidly reduced depressive symptoms in 34 adults with major depressive disorder, according to a clinical trial published in Nature Medicine. The improvements, which continued over the ensuing 2 weeks, suggest that this short-acting treatment could be a more practical therapy compared with other longer-acting psychedelic therapies.

Major depressive disorder is a leading cause of global disability, but many people do not respond to existing treatments, which are also associated with several side effects, including sexual dysfunction, weight gain, and sleep disturbance. Psychedelic-assisted therapy, including approaches using psilocybin (a compound found in magic mushrooms), has shown promise. However, the psychedelic effects of psilocybin persist for around 2 hours, which has made therapeutic sessions long and difficult to scale up. In contrast, DMT is a fast-acting psychedelic drug that, when administered intravenously, causes a brief period of subjective psychedelic effects of around 30 minutes. However, whether such a rapid-acting psychedelic could provide similar antidepressant effects to psilocybin has been unclear.

David Erritzoe and colleagues conducted a two-stage clinical phase 2 trial involving 34 adults with major depressive disorder. Participants were randomly assigned to receive either DMT or a placebo in the first, blinded stage. This was followed 2 weeks later by an open-label stage (participants and researchers knew what treatment was being administered) in which all the participants could receive DMT with therapist support. After 2 weeks, those who had received DMT in the first stage showed a greater reduction in depression scores on a clinical diagnostic tool called the Montgomery-Åsberg Depression Rating Scale, compared to those who had received the placebo, and improvements were already apparent after 1 week. During the open-label phase, antidepressant effects lasted for 12 weeks and no difference in Montgomery-Åsberg Depression Rating Scale scores were observed between participants who had received one dose than those who had received two. Most adverse events were mild or moderate — such as infusion-site pain, nausea or temporary anxiety — and no serious treatment-related adverse events were reported.

The authors note that larger studies are needed to confirm how effective DMT is for treating major depression, how long the benefits last, and how it compares with other existing therapies.