Severe depression is a disorder that can most often be improved with present day oral antidepressants. These drugs generally work by increasing the
amount of serotonin or norepinepherine in the brain. While effective in most patients, these medications can take weeks to begin working. In addition, your psychiatrist may have to try several different antidepressants before finding the right drug or combination of drugs that will help you. For patients with severe depression, or those having thoughts of self harm, the wait may be too long. For these patients, immediate relief of their depression is needed and may even be life saving. Until now, electro convulsive therapy (ECT) has been the only proven method of treating severe and life threatening depression with minimal delay.
For over a decade scientists have been studying the role of another neurotransmitter, glutamate, and its role in understanding depression. It has now been proven that the administration of subanesthetic doses of ketamine, a glutamate (NMDA) receptor antagonist, results in a dramatic and rapid improvement in severe depression.