Side effects of long-term treatment with fluoxetine.

Depressive disorders are frequently managed with long-term use of antidepressant medication. Even though the newer generation of selective serotonin reuptake inhibitor antidepressants exhibits a more favorable short-term, side-effect profile, effects of chronic use of such drugs remain unknown. Considering the limited data available on long-term, selective serotonin reuptake inhibitor management, we report for the first time on two cases of late-onset adverse effects occurring 6 and 10 years after chronic-fluoxetine treatment in which patients experienced symptoms of restlessness, tension, agitation, and sleep disturbances. Symptoms resolved after reduction or cessation of the medication. Our case reports suggest the existence of a late-onset side-effect profile, which appears similar to acute side-effect symptomatology. Super sensitivity of the serotonin-related receptors may develop over the long-term and account for the phenomenon. Careful clinical monitoring is recommended to detect any late-onset, medication-related side effects.