Mirtazapine-induced serotonin syndrome.
An 85-year-old woman developed sudden confusion and dysarthria progressing to mutism, orobuccal dyskinesias, generalized tremors worse with activity, ataxia, and rigidity with cog wheeling without high-grade fevers or dysautonomia. These findings were related temporally to the institution of mirtazapine as monotherapy for a major depressive illness with superimposed anxiety disorder. Withdrawal of the agent resulted in early notable clinical resolution with only residual hypertonia after 2 weeks. This is a rare report of serotonin syndrome induced by mirtazapine monotherapy. The hypothesized pathophysiologic mechanism in this case is overstimulation of serotonin (5-hydroxytryptamine or 5-HT) type 1A receptors (5-HT(1A)) in the brainstem and spinal cord in an individual with risk factors for hyperserotoninemia resulting from reduced, acquired endogenous serotonin metabolism.
Ubogu
Eroboghene E
EE
Division of Neuromuscular Diseases, Department of Neurology, Case Western Reserve University School of Medicine and University Hospitals of Cleveland, Hanna House 5th Floor, 11000 Euclid Avenue, Cleveland, OH 44106-5040, USA. eeubogu@excite.com
Katirji
Bashar
B
D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008803:Mianserin / Q000009:adverse effects* / Q000031:analogs & derivatives; D000078785:Mirtazapine; D020230:Serotonin Syndrome / Q000139:chemically induced* / Q000175:diagnosis
D008803:Mianserin; D000078785:Mirtazapine