What is ketamine, the drug tied to actor Matthew Perry's death?

 The use of the drug ketamine has evolved since its development in the 1960s as a human and animal anesthetic. Today, it's known both as a promising new treatment for severe depression and as a psychedelic party drug.

It's also now tied to the 

The actor died from the acute effects of the mind-bending drug, ketami  The 54-year-old accidentally drowned at his Los Angeles home.

Here's more information about ketamine.

Ketamine has been known to treat serious depression

In 2006, researches at the National Institutes of Health should  that an intravenous dose of ketamine could relieve severe depression in a matter of hours. That's compared to other remedies for depression, like Prozac and Zoloft, that often take weeks to ease the condition and don't work for everyIn 2018, Dr. Martin Teicher, an associate professor of psychiatry at Harvard Medical School and director of the Developmental Biopsychiatry Research Program at McLean Hospital that he considered the new uses of ketamine as "actually one of the biggest advances in psychiatry in a very long time."

And in , a nasal spray and the first antidepressant based on ketamine.

But even though ketamine works quickly, the effects wane after a few days or weeks, research has shown.

Perry himself was using ketamine infusion therapy for depression and anxiety, with the most recent infusion provided a week and a half before his death, his autopsy report said. But the ketamine used for that therapy was unlikely the cause of Perry' death as the half-life of the drug in the system is around three to four hours or less, the report said.

It's unclear still how or when Perry received more ketamine in the hours before he die to use ketamine to treat other psychiatric problems like substance use disorders and PTSD.

Researchers are also trying to extend ketamine's effects. that the drug given to patients who play computer games designed to boost self-esteem after a ketamine infusion appeared to prolong the benefits of the anesthetic for up to three months after the therapy