You may have heard recently that ketamine, an anesthetic medication, may be a promising treatment for depression. There have been no new drugs that treat depression in a unique way in decades, but ketamine works in a different way in the brain than traditional antidepressants.
Ketamine blocks a chemical called glutamate in the brain, which is different from the action of many antidepressants. Most antidepressants work on the neurotransmitters, of which serotonin is the most well known. Ketamine can help put a patient to sleep for surgery or relieve a patient who is in pain by placing them in a kind of trance called ‘dissociative anesthesia’. For this reason, the drug can also be abused, helping those who wish to leave reality; the drug can also cause hallucinations similar to PCP.
Small studies of 6-33 patients receiving low-dose ketamine have shown impressive results in reducing depression and suicidal thinking. One study showed improvements in depression within 40 minutes! Others showed improvement within hours to days, which is much shorter than the weeks to months traditional antidepressants or psychotherapy can take to have an effect. The effect lasted 7-10 days in some trials.
Studies in animals have shown increases in hormones and neurotransmitters that promote growth of brain cells. This is similar to how traditional antidepressants are thought to work, but it appears to happen much more quickly with ketamine. Ketamine may activate areas of the brain that are slowed in depression by increasing blood flow and consumption of blood sugar.
Larger, more rigorous studies are needed and are currently being conducted. One study hopes to compare ketamine with another anesthetic in 72 persons and should be completed later this year. Patients will be followed for up to 8 weeks. Although the research is preliminary, and abuse concerns are real, ketamine appears to have a bright future.