Antidepressant discontinuation syndrome

Antidepressant discontinuation syndrome, also called antidepressant withdrawal syndrome, is a condition that can occur following the interruption, reduction, or discontinuation of antidepressant medication following its continuous use of at least a month. The symptoms may include flu-like symptoms, trouble sleeping, nausea, poor balance, sensory changes, akathisia, intrusive thoughts, depersonalization and derealization, mania, anxiety, and depression. The problem usually begins within three days and may last for several weeks or months. Rarely psychosis may occur.

A discontinuation syndrome can occur after stopping any antidepressant including selective serotonin reuptake inhibitors (SSRIs), serotonin–norepinephrine reuptake inhibitors (SNRIs), monoamine oxidase inhibitors (MAOIs) and tricyclic antidepressants (TCAs). The risk is greater among those who have taken the medication for longer and when the medication in question has a short half-life. The underlying reason for its occurrence is unclear. The diagnosis is based on the symptoms.

Methods of prevention include gradually decreasing the dose among those who wish to stop, though it is possible for symptoms to occur with tapering. Treatment may include restarting the medication and slowly decreasing the dose. People may also be switched to the long acting antidepressant fluoxetine which can then be gradually decreased.

Approximately 20–50% of people who suddenly stop an antidepressant develop an antidepressant discontinuation syndrome. The condition is generally not serious, though about half of people with symptoms describe them as severe. Many restart antidepressants due to the severity of the symptoms.

Antidepressant discontinuation syndrome is a relatively new phenomenon, with its discovery in the 1950s. There is still little research on this syndrome; most of the research is conflicting or consists only of clinical trials. There has been a class action lawsuit in 2013, but the motion was dismissed.