Serotonin Syndrome Associated with a Duloxetine-Ciprofloxacin Combination: A Case Report

Abstract

Serotonin syndrome (SS) is a potentially life-threatening adverse drug reaction caused by excessive serotonergic agonism. SS is the result of overstimulation of 5-HT1A receptors by serotonergic agents. The symptoms are characterized by a triad of neuroexcitatory features, which include neuromuscular hyperactivity, autonomic hyperactivity, and altered mental status. Many drugs have been associated with SS mainly antidepressants such as selective serotonin reuptake inhibitors (SSRI), monoamine oxidase inhibitors (MAOI), and tricyclic antidepressants (TCA). SS usually occurs when these agents are used in combination or at high doses. Moreover, the addition of drugs that inhibit cytochrome P450 to a medication regimen which includes theses antidepressants has been associated with SS by increasing the serotonin concentration. Here, we report a case of SS as a result of the pharmacokinetic interaction between duloxetine and ciprofloxacin. To the best of our knowledge, this is the first report of SS associated with the duloxetine and ciprofloxacin combination.