Reactions 1313 - 7 Aug 2010

SCitalopram

Serotonin syndrome in an elderly patient: casereport

A 74-year-old woman with Alzheimer’s disease andbehavioural problems developed serotonin syndromeduring treatment with citalopram for depression.

The woman had been maintained on citalopram40 mg/day for 1 year [route of administration not stated],and had begun risperidone one day before admission forbehavioural symptoms. She had recently developeddiarrhoea. On admission she was confused, oriented onlyto person, with fluent but content-poor speech. Her dosageof risperidone was increased and she was treated withprochlorperazine for nausea and vomiting on day 3. Shesubsequently developed worsening tremor in her limbs,present with action or at rest, and a worsening shuffling gaitwith marked instability. Neurological examination 6 daysafter symptom onset revealed diffuse myoclonus involvingall four limbs, and intermittent myoclonus of her face, mild-to-moderate non-spastic limb rigidity, generalisedhyperreflexia and marked unsteadiness. She was orientedonly to person. Her unsteadiness worsened such that shecould no longer walk. Laboratory investigations revealedacute renal failure and mildly abnormal liver function11 days after admission. The following day she alsodeveloped fever and diaphoresis. Serotonergic toxicity dueto poor renal function was suspected.

Intravenous volume replacement was commenced andcitalopram was discontinued; she had received citalopramfor 10 days since admission. The woman’s BUN andcreatinine levels returned to baseline and after several days,her symptoms resolved completely. Her liver enzymes hadnormalised 3 weeks later.

Author comment: "Based on the Naranjo scale, thispatient’s clinical manifestations were possibly due to anadverse drug reaction secondary to citalopram."Yee AH, et al. A perfect storm in the emergency department. Neurocritical Care12: 258-60, No. 2, Apr 2010 - USA 803029535

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Reactions 7 Aug 2010 No. 13130114-9954/10/1313-0001/$14.95 © 2010 Adis Data Information BV. All rights reserved