It activates mu-opioid quite strongly but not the other receptors as much (I forget their names). Interestingly, it has a mix of opioid antagonists and agonist

It activates mu-opioid quite strongly but not the other receptors as much (I forget their names). Interestingly, it has a mix of opioid antagonists and agonists. I’m not sure if that specifically is why tolerance doesn’t build aggressively, or if it’s some other MoA like nmda receptor antagonism