People usually take antidepressants for a few weeks before they start to work. Those medicines need to build up in your system to have an effect.
Ketamine is different. Its effects on depression happen as it leaves your body, Krystal says.
Researchers aren’t sure exactly why that is. One theory is that ketamine prompts connections to regrow between brain cells that are involved in mood. Krystal calls the effect “profound” and says the drug works “far more rapidly” than today’s antidepressant pills.
The director of the National Institute of Mental Health agrees. “Recent data suggest that ketamine, given intravenously, might be the most important breakthrough in antidepressant treatment in decades,” says Thomas Insel, MD.
One day, doctors may use ketamine to help severely depressed people until other antidepressants start to work. But as a cousin of the psychedelic drug PCP, you would never get it at your local pharmacy.
“While the science is promising, ketamine is not ready for broad use in the clinic. We just don’t know enough. But with the excitement generated by early results, we will have more information soon,” Insel says.
Ketamine still has a shadowy side — its use as a street drug, where the risks can quickly spin out of control.