A separate, smaller experiment that was included in the Nature Medicine paper appeared to support the notion that psilocybin therapy could provide enduring benefits. In that trial, 16 patients were recruited with the knowledge that they would receive psilocybin for their treatment-resistant depression. Brain scans taken a day after the final doses were administered showed similar results to the other study. And when the researchers followed up six months later, many participants reported that the improvements to their depression had not subsided.
“These results are very promising, but obviously no one should go out and try and procure psychedelics without speaking to a doctor or a therapist,” Dr. Daws said.
The field of psychedelic medicine is still in its infancy following a decades-long gap in research, a direct result of antidrug policies that prevented most scientists in the United States from investigating mind-altering compounds. But as the stigma has faded and research funding has begun to flow more freely, a growing number of scientists have begun exploring whether such drugs can help patients suffering from a wide range of mental health conditions, including anorexia, substance abuse and obsessive-compulsive disorder.
Along with psilocybin, MDMA, popularly known as Ecstasy, has been especially promising. A study last May in Nature Medicine found that the drug paired with talk therapy could significantly lessen or even eliminate symptoms of PTSD. Phase 3 clinical trials are now underway, and some experts believe the Food and Drug Administration could approve MDMA therapy for PTSD as soon as next year.
Depression remains one of most common and intractable mental health challenges in the United States, with an estimated 21 million adults reporting a major depressive episode in 2020, according to the National Institute of Mental Health. Although Prozac and other antidepressants known as S.S.R.I.s have been effective for many, they have significant side effects and the drugs do not work for everyone.
For that reason, the handful of small studies on psilocybin and depression have electrified mental health experts and patients.
Another author of the Nature Medicine article published on Monday, Robin Carhart-Harris, director of the Neuroscape Psychedelics Division at the University of California, San Francisco, said the functional magnetic resonance imaging scans offered intriguing clues about the way depression inhabits the brain. The resulting images, he suggested, might be best compared to an undulating pastoral landscape marked by hills and deep valleys. People with depression, he said, often get stuck in a valley. Although S.S.R.I.s can make them feel better, the drugs do not appear to change the overall landscape of their brain, as it were, suggesting that the drugs do little more than ease the symptoms of their depression.