Ketamine -- or, as it is known in the rave scene, "Special K" -- is proving to be an effective treatment for major depressive disorders that were once considered treatment-resistant, Nature reports.
The drug is a potent anesthetic, but a recent study in Translational Psychiatry suggests that it also increases the ability of neurons to bind with serotonin -- the so-called "feel good neurotransmitter" -- in the parts of the brain that regulate motivation.
Almost 40 percent of individuals suffering from depression do not respond to drugs like serotonin reuptake inhibitors, monoamine oxidase inhibitors, and tricyclic antidepressants -- and for those that do, it often sometimes takes weeks or months for the drugs to have an effect.
Ketamine, however, begins to lift depression in as little as two hours, making it an ideal drug to use for people in the throes of a suicidal episode.
Psychiatrist James Murrough at Mount Sinai Hospital in New York City told Nature that this "blew the doors off what we thought we know about depression treatment."
"The rapid therapeutic response of ketamine in treatment-resistant patients is the biggest breakthrough in depression research in a half century. It's like a magic drug -- one dose can work rapidly and last for seven to 10 days," added Ronald Duman, a professor of psychiatry and pharmacology at Yale and lead author of an earlier study on its effectiveness in rapidly treating depression.
That study found that 70 percent of individuals resistant to other forms of drug therapy responded to ketamine within hours. It also demonstrated that ketamine triggers the release of the neurotransmitter glutamate, which stimulates the growth of synapses -- and that damage to synapses caused by chronic stress can be reversed by a single dose of ketamine.
Early this year, Carlos Zarate of the National Institute of Mental Health and his team will begin a multi-year study of suicidal patients, some of whom will enrolled in a clinical trial of ketamine, in order to better understand both the drug's effect and what an actively suicidal brain looks like.
