Posted by Shawn. T. on August 25, 2005, at 15:10:14
In reply to Dextromethorphan? Why?, posted by Empathy on August 25, 2005, at 1:19:51
Dextromethorphan (DXM) exhibits relatively high affinity binding activity as a sigma-1 receptor agonist and serotonin reuptake inhibitor. DXM is also a low affinity, noncompetitive NMDA receptor antagonist. The active metabolite of DXM, dextrorphan, is a more potent noncompetitive NMDA antagonist and sigma-1 agonist than DXM. In addition, dextrorphan is a serotonin reuptake inhibitor. Dextrorphan and DXM also bind with low affinity to sigma-2 receptors. DXM and dextrorphan noncompetitively block alpha3beta4 neuronal nicotinic acetylcholine receptors; other nicotinic receptor subtypes may also be affected by these drugs. Serotonin reuptake, sigma-1 agonism, and NMDA antagonism are all mechanisms of action that can lead to an antidepressant effect. Also, DXM is not an opiate.