The discrepancy between the short half-life of ketamine and its long-lasting effects is due to ketamine being trapped in NMDA receptors, and its release depends on neural activity in the lateral habenula. Ketamine, an N -methyl- d -aspartate receptor (NMDAR) antagonist^ 1 , has revolutionized the treatment of depression because of its potent, rapid and sustained antidepressant effects^ 2 – 4 ....