Linezolid-Associated Serotonin Syndrome. A Report of Two Cases.

Linezolid, a mild monoamine oxidase inhibitor, is a commonly used antibiotic drug for the treatment of complicated skin and skin structure infections, including diabetic foot infections. Use of linezolid has been associated with serotonin syndrome, a potentially life-threatening condition typically caused by the combination of two or more medications with serotonergic properties, due to increased serotonin release. The goals of this article are to highlight the risk factors associated with the development of serotonin syndrome related to the use of linezolid and to aid in its prevention and early diagnosis. In this case series we report on two hospitalized patients who, while being treated with linezolid for pedal infections, developed serotonin syndrome. Both individuals were also undergoing treatment with at least one serotonergic agent for depression and had received this medication within 2 weeks of starting the antibiotic drug therapy. In these individuals, we noted agitation, confusion, tremors, and tachycardia within a few days of initiation of linezolid therapy. Owing to the risk of serotonin toxicity, care should be taken when prescribing linezolid in conjunction with any other serotonergic agent. Although serotonin syndrome is an infrequent complication, it can be potentially life threatening. Therefore, risks and benefits of therapy should be weighed before use.