Could the psychedelic drug DMT improve mental health? Original paper

In a nonrandomized placebo-controlled trial and a noncontrolled trial, the drug N,N-dimethyltryptamine (aka DMT) reduced symptoms of depression and trait neuroticism in adults at 1 to 2 weeks after administration.

The effects of the psychedelic drug N,N-dimethyltryptamine (DMT) on mental health outcomes.

The primary outcomes were negative psychological factors, including depression severity, trait anxiety, and trait neuroticism; these were assessed using the Quick Inventory for Depressive Symptomatology (QIDS-SR16), State-Trait Anxiety Inventory (STAI-T), and the Neuroticism-Extraversion-Openness Five-Factor Inventory (NEO-FFI), respectively.

The secondary outcomes included positive psychological factors (i.e., well-being, optimism, nature-relatedness, gratitude, and meaning in life) and the acute subjective effects of DMT (e.g., peak or mystical-type experiences).

30 adults (average age of 34) with no known health conditions, all of whom had previous experience with psychedelic drugs.

A total of 13 participants completed a nonrandomized placebo-controlled trial (average age of 34; 6 women and 7 men), and 25 participants completed a noncontrolled trial (a type of before-and-after study) (average age of 34; 10 women and 15 men).

In the placebo-controlled trial, the participants received a placebo intravenous (IV) injection of saline and (7 days later), they received an IV injection of DMT.

Three volunteers received a 7 milligram (mg) dose of DMT, 4 received a 14 mg dose, 1 received an 18 mg dose, and 5 received a 20 mg dose.

The participants rated their subjective experience of the drug (or placebo) at 20 minutes after the injection using the 5-Dimensional Altered States of Consciousness Questionnaire (5DASC). Mental health outcomes were assessed at baseline (before the placebo), 1 week after the placebo injection, and 1 week after the DMT injection.

In the noncontrolled trial, the participants received a placebo IV injection and a DMT IV injection on 2 separate visits. The order of the injection was different at each visit (i.e., a participant who received the placebo first then DMT on the first visit received DMT and then the placebo on the second visit). All of the participants completed mental health questionnaires at baseline and 2 weeks after the first session.

Overall, depression was reduced after DMT. In the placebo-controlled study, trait neuroticism was reduced (improved) 1 week after DMT, compared to the placebo condition.

DMT led to higher subjective ratings of Oceanic Boundlessness, Dread of Ego-Dissolution, Visual Restructuralization, and Auditory Alterations (items on the 5D-ASC). These subjective changes were associated with greater improvements in depression severity and trait anxiety 1 to 2 weeks after DMT administration.

No changes in positive psychological factors were observed in either study.

The association between the subjective acute effects of DMT and improvements in depression and anxiety should be interpreted cautiously. The results from the placebo-controlled trial and the noncontrolled trial were combined, meaning that there was considerable variability in the dose of DMT and the timing of the measures.