ketamine

In zebrafish, ketamine causes changes a brain circuit involved in "giving up." That may help explain how the drug helps people with depression.

Ketamine, approved as an anesthetic in 1970, is emerging as a major alternative mental health treatment. But more than 500 clinics have popped up with little regulation, and treatment varies widely.

Researchers were able to mimic the mind-altering effects of the drug ketamine by inducing a particular rhythm in one area of the brain.

Participants in the U.K. experimental study dramatically reduced their average alcohol intake for months after the initial dose. Ketamine has also been used to treat severe depression.

Doctors and patients are using ketamine to treat severe depression, even though the anesthetic and psychedelic club drug has not been approved by the FDA for that purpose. It's not without risks.