Reactions 1176 - 3 Nov 2007

SCitalopram

Inappropriate antidiuretic hormone secretion: casereport

A 54-year-old woman, who had hypertension and was on asalt-restricted diet, developed syndrome of inappropriatesecretion of antidiuretic hormone (SIADH) during treatmentwith citalopram.

The woman, who had been on a salt-restricted diet for6 months, started receiving citalopram 20 mg/day for worriesand a depressed mood; concomitant medications includedcarvedilol and candesartan cilexetil. Ten days later, shereported drowsiness, paraesthesia, nausea, vomiting, visualhallucinations and fatigue and was hospitalised; Two daysearlier, she had reported her symptoms to relatives and haddiscontinued citalopram. At presentation, she appearedeuvolemic. Laboratory investigations revealed a serum sodiumlevel of 97.4 mmol/L and a potassium level of 2.28 mmol/L.She also had serum hypo-osmolality, an elevated urine sodiumlevel and urine hyperosmolality, which supported a diagnosisof SIADH. Psychiatric examination showed drowsiness, severeconfusion, delusional thoughts, visual hallucinations andslurred speech.

The woman was placed under fluid restriction and receivedan infusion of hypertonic saline. Six days after admission, herserum sodium level normalised and her symptoms resolved.At discharge, she had a serum sodium level of 137.2 mmol/Land a potassium level of 5.19 mmol/L. One week afterdischarge, she denied any symptoms and psychiatricexamination only revealed an anxious mood and mildly slurredspeech.

Author comment: "Due to the temporal relationshipbetween initiation of citalopram therapy and thedevelopment of SIADH as well as the exclusion of otheraetiologies and return of laboratory levels to normal afterdiscontinuation of citalopram, the most likely cause wascitalopram."Bez Y, et al. Citalopram-induced SIADH in a hypertensive patient on saltrestricted diet. Journal of Psychopharmacology 21: 665-667, No. 6, Aug 2007 -Turkey 801097129

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Reactions 3 Nov 2007 No. 11760114-9954/10/1176-0001/$14.95 Adis © 2010 Springer International Publishing AG. All rights reserved