Yeah, ketamine is used as a sedative and painkiller in people who don't tolerate opioids. It's used off-label in low doses for treatment of depression and chronic migraines -- though is almost always administered by a doctor in a structured theraputic regimen.
The success of an approved drug like ketamine in treating depression and chronic migraines has opened the doors for studying other hallucinogens.
Clinical trials are happening for mushrooms as well.