Serotonin syndrome – ‘potential’ role of the CYP2D6 genetic polymorphism in Asians

The serotonin syndrome is thought to be caused by excess serotonin availability in the CNS, especially at the 5-HT-1A receptor (Sternbach, 1991). Although the syndrome is produced most often by the concurrent use of monoamine oxidase inhibitors and other serotonergic agents (Sternbach, 1991), more recent reports suggest that selective serotonin reuptake inhibitor (SSRI) monotherapy induces the syndrome (Bastani et al., 1996; Fischer, 1995; Gill et al., 1999; Lenzi et al., 1993). For the SSRI paroxetine, there is only one case report of serotonin syndrome connected with its sole use (Cavallazzi and Grezesiuk, 1999). We report here on the rare case of a patient who developed the syndrome after receiving a single dose of paroxetine.