After some people stop taking a type of antidepressant known as a selective serotonin reuptake inhibitor (SSRI), they experience a variety of symptoms. According to Dr. Ross J. Baldessarini, professor of psychiatry and neuroscience at Harvard Medical School and director of the psychopharmacology program at McLean Hospital, these symptoms may include “a flu-like reaction, as well as a variety of physical symptoms, that may include headache, gastrointestinal distress, faintness and strange sensations of vision or touch.”
This common phenomenon is known as SSRI discontinuation syndrome. (It may also be known as SSRI withdrawal syndrome.)
Discontinuation symptoms typically arise within days after stopping the medication, particularly if it was stopped abruptly. Stopping a high dose of a relatively short-acting drug also can bring on symptoms. In addition to the previously-mentioned symptoms, “anxiety and depressed or irritable mood are common features that may make it hard to differentiate SSRI discontinuation syndrome from early return of symptoms of depression,” Baldessarini said.
However, the risk for discontinuation syndrome is generally greater with potent, short-acting SSRIs —particularly paroxetine (Paxil and others) and venlafaxine (Effexor and others), Baldessarini said.
Discontinuation symptoms can happen with any antidepressant, but seem to be more common with the following classes of drugs:
SSRIs. These include citalopram (Celexa), escitalopram (Lexapro), fluoxetine (Prozac and others), fluvoxamine (Luvox), paroxetine (Paxil), and sertraline (Zoloft)
Inhibitors of inactivation of both norepinephrine and serotonin (SNRIs). These include chlompramine (Anafranil), venlafaxine (Effexor) and desvenlafaxine (Pristiq). Such drugs are prescribed more often for depression or severe anxiety disorders, so the withdrawal phenomenon is more common.
Whether you experience discontinuation syndrome after stopping an SSRI depends on several factors. These include the amount of time you’ve taken the medication, your dosage level, and the pill’s half-life (how quickly it is eliminated from your body). For instance, Prozac, which has about a five-week half-life, appears to cause discontinuation much less often than drugs with shorter half-lives, such as Paxil.
If discontinuation symptoms last more than a week or two, call your doctor. You may be in the early stages of a relapse.