text: Ligand-gated ion channels are likely to be the major site at which anaesthetic agents and ethanol have their effects, although unequivocal evidence of this is yet to be established.  In particular, the GABA and NMDA receptors are affected by anaesthetic agents at concentrations similar to those used in clinical anaesthesia.
  By understanding the mechanism and exploring the chemical/biological/physical component that could function on those receptors, more and more clinical applications are proven by preliminary experiments or FDA. Memantine is approved by the U.S. F.D.A and the European Medicines Agency for the treatment of moderate-to-severe Alzheimers disease, and has now received a limited recommendation by the UKs National Institute for Health and Care Excellence for patients who fail other treatment options. Agomelatine, is a type of drug that acts on a dual melatonergic-serotonergic pathway, which have shown its efficacy in the treatment of anxious depression during clinical trials, study also suggests the efficacy in the treatment of atypical and melancholic depression.