Thursday January 12, 2006
LINEZOLID & SEROTONIN SYNDROME 3

Linezolid (Zyvox) being a reversible, nonselective monoamine oxidase inhibitors (MAOIs) can cause a serious serotonin syndrome if use concomittently with antidepressents citalopram (Celexa) 2, sertraline (Zoloft), fluoxetine (Prozac), and paroxetine (Paxil) . Case has been reported with use of linezolid 18 days after the discontinuation of fluoxetine. Norfluoxetine (fluoxetine’s active metabolite) is thought to be the culprit. 1

Being an intensivist it is a very important drug interaction need to be aware of as most patients admitted to ICU from long term care may be on antidepressents and may require Zyvox for MRSA treatment. Related: See brief review on Serotonin syndrome here from McGill University, Montreal. CMAJ • May 27, 2003; 168 (11) followed with letter Serotonin syndrome: not a benign toxidrome CMAJ • September 16, 2003; 169 (6). It was discussed in detail in our related pearl on Dec. 31, 2005

References: Click to get abstract or article
1. Serotonin Syndrome Associated With Linezolid Treatment After Discontinuation of Fluoxetine - Psychosomatics 46:274-275, June 2005
2. Serotonin Syndrome after Concomitant Treatment with Linezolid and Citalopram - Clinical Infectious Diseases, volume 36 (2003), page 1197 - pdf file
3. Serotonin Syndrome and Linezolid - Clinical Infectious Diseases, volume 34 (2002), pages 1651–1652 - pdf file
4. The Serotonin Syndrome - NEJM, March 2005 Volume 352:1112-1120