Disposition of citalopram in biological specimens from postmortem cases

Citalopram is a bicyclic phthalate compound approved in 1998 by the U.S. Food and Drug Administration for the treatment of depression. It is a highly selective serotonin reuptake inhibitor that appears to have little effect on noradrenaline or dopamine reuptake. Since this drug has only recently been released on the U.S. market, information regarding therapeutic, toxic, and lethal concentrations is sparse. This study reports the detection of citalopram in 22 postmortem cases. Citalopram was identified and quantitated by capillary column gas chromatography with nitrogen phosphorus detection after basic liquid-liquid extraction. Confirmation was achieved by full scan electron impact gas chromatography/mass spectrometry. In the 22 cases studied, heart blood citalopram concentrations ranged from 0.09 to 1.64 mg/L (n = 22, mean +/- SD = 0.51+/-0.43, median = 0.34); femoral blood concentrations ranged from 0.09 to 0.76 mg/L (n = 14, mean +/- SD = 0.34+/-0.23, median = 0.28); and urine concentrations ranged from 0.05 to 276.00 mg/L (n = 13). Liver was analyzed in three cases with citalopram concentrations ranging from 2.22 to 8.08 mg/kg. The average heart blood/femoral blood ratio was 1.26 (range 0.75 to 1.98, n = 14). In each case, the cause of death was not considered to be related to citalopram toxicity. These data may therefore provide a basis for establishing post mortem citalopram concentrations following therapeutic doses.