It is one of the most common and wrenching decisions in mental health: when to stop antidepressant medication.

The big risk of going off the drugs is the possibility of relapse. Those who have had one episode of depression have a 50% chance of having a second. Those who have had two episodes have an 80% chance of having another. Continuing on antidepressant medication can cut the risk of relapse in half, according to a review of 15 clinical trials that was published in the Journal of Clinical Psychiatry in 2014.

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