Psychedelics are not intoxicants in the usual sense; they do not dull a person’s senses or induce sleepiness. Side effects include temporary changes in sensory perception and diminished coordination and fine-motor function. These occur mostly during the first few hours of a session. The drugs are not toxic to the brain or other organs. “Bad trips,” the terrifying episodes of panic that occasionally occurred during recreational use of these drugs, are exceedingly rare when the psychedelics LSD or psilocybin are administered in monitored, supportive settings and patients are prepared in pre-session counseling.

In contrast to currently approved antidepressants, which must be taken daily and typically require weeks to take effect (or not), psychedelics are administered in medically supervised settings, usually during one or two six-hour sessions, and their therapeutic effects are immediate. In clinical studies, as many as 80 percent of patients experienced substantial relief from depression, including those whose illness had persisted through multiple courses of treatments. The neuropharmacological and psychological mechanisms for the improvements in people’s mental health are also different from those of existing anti-depressants. Research subjects commonly described a shift to a more positive worldview, accompanied by a deepened sense of meaning and connection to others, and an enhanced appreciation for the intrinsic value of their lives. Notably, the benefits often endure for many months after even a single treatment.