Distribution of carbamazepine and its metabolites carbamazepine-10,11-epoxide and iminostilbene in body fluids and organ tissues in five autopsy cases

Carbamazepine (CMZ) and its metabolites, carbamazepine-10,11-epoxide (CMZepo) and 2,2'-iminostilbene (Imi), were simultaneously assayed by gas chromatography-mass spectrometry (GC-MS) in body fluids and organ tissues taken from victims in five autopsy cases. Clomipramine-HCl was added to each specimen as internal standard (IS); target compounds and IS were simultaneously extracted with an Extrelut NT column before analysis by GC-MS. The concentrations of CMZ were generally much higher in organ tissues than in blood and urine, and were higher in the liver than in the lung in three cases. The concentrations of metabolites CMZepo and Imi were lower than those of CMZ in all body fluid and organ tissue specimens; the Imi concentrations in the brain were higher than CMZepo concentrations in four cases. Imi concentrations in the kidney, however, were lower than those of CMZepo in four cases. In the lung and liver, the concentrations of Imi did not show a consistent trend; those of Imi were higher or lower than those of CMZepo, but both metabolites were not at negligible levels. To our knowledge, this is the first demonstration of the distribution of Imi among human body fluids and tissues.