A recent study published in the Archives of General Psychiatry by researchers at National Institute of Mental Health showed that the medication Ketamine, given intravenously to a small group of people with bipolar depression, caused a rapid antidepressant response in a high percentage of those patients. Their responses were much better than patients given a placebo IV solution.

The purpose of this study was to look at a specific type of neurotransmitter – glutamate – that is different than any of the transmitters that our current medications target. The question being asked was whether targeting these particular receptors might provide more rapid relief of depressive symptoms specifically in people with bipolar depression. There have been several previous studies showing a rapid, strong antidepressant response to IV-administered Ketamine in people with depression, but this is the first study to look at these receptors in bipolar depression specifically.

The benefits from the Ketamine lasted an average of 6.8 days, and while one patient on Ketamine became manic, so did one patient on placebo. The side effects included some initial periods of dissociation and changes in perception – these effects were brief, and not everyone experienced them.

Ketamine is used recreationally (as the club drug known as Special K) to get these perceptual and dissociative feelings. This is not discussed in the study but is something to be considered if Ketamine is going to be further evaluated as a potential treatment for depression.

The study is valuable because it adds something to our understanding of the neurochemistry of bipolar disorder and possible new treatment approaches. This study isn’t suggesting that intravenous Ketamine be used in a clinical setting to treat bipolar depression, but it is expanding our knowledge of ways to treat it – and in particular – possibly ways to treat depression much more quickly than we do with our currently available medications. There is a lot of active research on the glutamate system and it is likely to be the next big wave of new interventions for depression.