Pursuit of Ketamine examines this legal medicine to treat depression and pain. Featuring Dr. Sam Ko and two patients, this series provide "real life" information to people who may be suffering from severe maladies. More than 50 million Americans suffer from chronic pain. More than 17 million suffer high-impact chronic pain. Nearly 20% suffer from depression. Standard therapies are not bringing relief. Yet ketamine, in use since 1970, has been a powerful benefit for many pain and depression sufferers.