FDA Approves Esketamine for TRD

The treatment is in the form of a nasal spray containing ketamine.

Technically, the anesthetic ketamine is not a hallucinogen because it is an antagonist of the serotonin 5-HT2A receptor. In other words, it blocks the receptor and does not cause an effect. Esketamine and its parent compound ketamine work via the NMDA (N-methyl-D-aspartate) receptor in nerve cells. However, ketamine is referred to as a psychedelic drug by researchers at a behavioral level because it does cause feelings of dissociation (out-of-body experience) and distortions of time and space.