Selective Serotonin-Reuptake Inhibitors (SSRIs)
Selective serotonin-reuptake inhibitors (SSRIs) are the first-line treatment for major depression. They work by increasing levels of serotonin in the brain. Because they act specifically on serotonin, SSRIs have fewer side effects than older antidepressants, which have more widespread effects in the body.
SSRIs include fluoxetine (Prozac, generic), sertraline (Zoloft, generic), paroxetine (Paxil, generic), fluvoxamine (Luvox, generic), citalopram (Celexa, generic), and escitalopram (Lexapro). There do not appear to be significant differences among SSRI brands in effectiveness, although individual drugs may have different side effects or benefits for specific patients.
At this time, fluoxetine and escitalopram are the only antidepressants approved for treatment of major depressive disorder in adolescents (ages 12 - 17). Fluoxetine is also approved for children age 8 and older.
Candidates for SSRIs. SSRIs appear to best help people with the following conditions:
- Mild-to-moderately severe major depression
- Seasonal affective disorder
- Severe premenstrual syndrome and premenstrual dysphoric disorder (PMDD). A repackaged form of fluoxetine (Sarafem) is the first SSRI specifically FDA-approved for PMDD. Other SSRIs and newer antidepressants are also proving to be effective.
- Anxiety disorders
Duration of Effectiveness and Use. SSRIs take, on average, 2 - 4 weeks to be effective in most adults. They may take even longer, up to 12 weeks, in the elderly and in those with dysthymia. By 14 weeks, depression should be in remission in those who respond to the drugs. Unfortunately, recurrence is common once the drugs are stopped. Studies indicate that the standard SSRIs are generally safe to be taken long term, although it is still unclear which patients most benefit from on-going medication. Some doctors recommend withdrawing from medication after a year. If depression recurs, then the patient should go back on the antidepressant.
Review Date: 01/27/2011
Reviewed By: Harvey Simon, MD, Editor-in-Chief, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.