POSTMORTEM CHANGES IN BLOOD AMITRIPTYLINE CONCENTRATION

Detailed toxicological studies were undertaken on two suicides by amit riptyline overdose, one with salicylate also. In the first case, 10 in itial blood samples taken 21 h after body discovery and an estimated 2 8 1/2 h after overdose had drug concentration (mg/L) ranges of 2.5-12 for amitriptyline (AM), 0.7-3.1 for nortriptyline (NOR), and 81-244 fo r salicylate (SAL). Ten blood samples taken 42 h later showed correspo nding ranges of 1-39 AM, 0.6-7.0 NOR, and 86-310 SAL. Sample haemoglob in concentrations (range, 8.7-23.5 g/dl) did not correlate with drug c oncentrations. Postmortem increase in pulmonary vein AM concentration occurred more rapidly than in the pulmonary artery, likely reflecting relative ease of diffusion across the vessel walls from lung (AM, 60 m g/kg). In nine tissue samples, drug concentrations (mg/kg) were highes t in the liver: AM, 301; and SAL, 670. Considerable drug residue was p resent in gastric contents, duodenal contents, and seven sequential sm all bowel contents. In both cases, sanguineous putrefactive pleural fl uid showed higher AM concentrations on the left than on the right (2.0 vs 1.4 and 23 vs 16), likely reflecting diffusion from gastric drug r esidue. The detailed case data illustrate the intensity and complexity of postmortem drug diffusion from reservoirs in solid organs, such as the lungs, and unabsorbed gastric residue, into the blood and putrefa ctive fluids.