The purpose of the study is to examine whether an investigational medication called ketamine
along with psychotherapy is an effective treatment for depression in participants with a
history of opioid addiction who have not abused opioids in at least 3 months. Participants
will receive ketamine through intramuscular injection along with psychotherapy weekly for 8
weeks. Participation for eligible subjects who decide to enroll (including post-medication
follow-up visits) will last about 16 weeks or 4 months.