Methoxetamine is a dissociative anaesthetic showing pharmacodynamic similarities with its analogue ketamine, a medication with demonstrated rapid-acting antidepressant effects. Like ketamine and other arylcyclohexylamine compounds, methoxetamine is thought to be both a noncompetitive NMDA receptor antagonist and a dopamine reuptake inhibitor. Furthermore, it acts as an agonist at dopamine D2, serotonin 5HT2, muscarinic cholinergic, sigma-1, opioid mu and k receptors. The hypothesis is that methoxetamine can produce rapid antidepressant effects in patients with resistant and non-resistant unipolar and bipolar depression.