NMDA receptor blockade by ketamine is likely responsible for longer-term mood changes and immediate effects like dissociation and euphoria in ketamine therapy.

“the nmda receptor blockade is critical for the neuroplastic changes that are going to occur over the days and weeks following ketamine treatment and if you think back to our earlier discussion when we were talking about the two time a week over three week type regimen of taking ketamine or some variant on that now it might start to make sense as to why yes there is immediate and short-term benefit of taking ketamine for depression in the clinically appropriate setting of course I'm not talking about recreational use right now but that also there's some durability of those effects that even after the three weeks of taking ketamine twice per week people often will experience weeks or months of relief from depression when they're not doing the weekly ketamine therapy sessions”