Depression is a chronic psychiatric disorder with a complex etiology. Currently used antidepressant drugs take at least several weeks to achieve a therapeutic response and this lag period increases a risk of suicide attempts. A significant percentage of patients, particularly those diagnosed with major depression, do not respond adequately to the first-line treatment with conventional antidepressants. In addition, antidepressant drugs exert numerous adverse effects that often leads to cessation of the therapy. Therefore, there is an urgent need to develop rapidly acting therapeutics with a better effectiveness and tolerability. Strong evidence, accumulated in recent several years, has shown that ketamine used in low, subanesthetic doses is an effective and fastacting antidepressant for a variety of depressed patients. This survey presents a summary of what is known about the antidepressant action of ketamine, and discusses risks associated with the use of this drug.

Keywords: ketamine, depression, antidepressant drugs, glutamatergic neurotransmission, synaptic plasticity.