Scientists in Brazil, the world's second-biggest consumer of cocaine, have announced the development of an innovative new treatment for addiction to the drug and its powerful derivative crack: a vaccine.

Exposure to cannabis in adolescence is associated with increased risk of psychiatric disorders. Here, in a mouse model of 16p11.2 duplication, the authors identified a role of microglial Cnr1 for mediating the adverse effect of THC exposure on mPFC maturation and social memory.

As the United States continues to grapple with a devastating opioid-involved overdose crisis, conservative policymakers have seized on a familiar ...

In this clinical trial, a single dose of intravenous ketamine delivered during surgical anesthesia had no greater effect than placebo in acutely reducing the severity of depressive symptoms in adults with major depressive disorder.

A limitation of this study is its post hoc, exploratory design; recommendations for further research are provided.

Psilocybin (a classic serotonergic psychedelic drug) has received appraisal for use in psychedelic-assisted therapy of several psychiatric disorders. A less explored topic concerns the use of repeated low doses of psychedelics, at a dose that is well below the psychedelic dose used in psychedelic-assisted therapy and often referred to as microdosing. Psilocybin microdose users frequently report increases in mental health, yet such reports are often highly biased and vulnerable to placebo effects. Here we establish and validate a psilocybin microdose-like regimen in rats with repeated low doses of psilocybin administration at a dose derived from occupancy at rat brain 5-HT2A receptors in vivo. The rats tolerated the repeated low doses of psilocybin well and did not manifest signs of anhedonia, anxiety, or altered locomotor activity. There were no deficits in pre-pulse inhibition of the startle reflex, nor did the treatment downregulate or desensitize the 5-HT2A receptors. However, the repeated low doses of psilocybin imparted resilience against the stress of multiple subcutaneous injections, and reduced the frequency of self-grooming, a proxy for human compulsive actions, while also increasing 5-HT7 receptor expression and synaptic density in the paraventricular nucleus of the thalamus. These results establish a well-validated regimen for further experiments probing the effects of repeated low doses of psilocybin. Results further substantiate anecdotal reports of the benefits of psilocybin microdosing as a therapeutic intervention, while pointing to a possible physiological mechanism.

The program was about education. But it was also about surveillance.