In 2016, I wrote Ketamine Research In A New Light, which discussed the emerging consensus that, contra existing theory, ketamine’s rapid-acting antidepressant effects had nothing to do with NMDA at all. I discussed some experiments which suggested they might actually be due to a related receptor, AMPA.

The latest development is Attenuation of Antidepressant Effects of Ketamine by Opioid Receptor Antagonism, which finds that the opioid-blocker naltrexone prevents ketamine’s antidepressant effects.