Acute Maniform Reaction to a Single Dose of Escitalopram in a Social Phobic Patient – An Atypical Jitteriness Syndrome?

We report an unusual acute mental side-effect [ 4 ] of the selective serotonin reuptake inhibitor (SSRI) escitalopram in a 23-year-old male student of mathematics, who has suffered from severe social fears and avoidance behaviour since kindergarten. He was diagnosed with social anxiety disorder (DSM-IV) and admitted for in-patient therapy. A structured diagnostic interview (SCID) revealed no psychiatric comorbidity, physical examination and laboratory work-up showed no peculiarities besides slight obesity. About one hour after the first dose of escitalopram (5 mg) he unexpectedly became giddy, chatty, kidding, vociferous, uncommonly gregarious, restless, incapable of controlling his thoughts and actions. After eight hours the symptoms subsided without any pharmacological intervention; escitalopram treatment was stopped. The patient abnegated intake of illegal drugs, no such substances could be detected in his blood or urine. One week later, when escitalopram was initiated a second time, only short-lived motor restlessness, trembling, fidgetiness and difficulty in concentrating emerged, but no maniform symptoms. Escitalopram was gradually increased to 15 mg/d without further side-effects during the following six weeks. Although it was assumed that a subset of social phobic patients might belong to the bipolar spectrum [ 3 ] [ 6 ] and overshoot during SSRIs in a hypomanic direction [ 2 ], the further course of this patient does not corroborate this possibility. Symptoms of behavioural activation and agitation have been reported in adolescent anxiety disorder patients after SSRIs [ 5 ], but only after a longer duration of treatment. The authors presume an underlying neuromaturational vulnerability and, of note, our patient possibly had suffered from night terrors as a child. We hypothesize that his initial symptoms might be an atypical manifestation of the “jitteriness syndrome” [ 1 ], which he experienced in a typical way during re-challenge with escitalopram. Agitation or jitteriness after acute SSRIs is possibly mediated by activation of 5-HT2C receptors [ 2 ]. However, we are not aware that brief maniform symptoms have so far been described as an atypical manifestation.