Interpretation of melperone intoxication: post-mortem concentration distribution and interpretation of intoxication data

Abstract

Abstract Objectives Since melperone abuse with lethal intoxication is common, expert opinions based on therapeutical and lethal concentration ranges can be considered as important. Because there is a lack of information about fatalities caused by melperone mono-intoxications and data on tissue samples with concentration distribution, the aim of this work is the examination of lethal concentration ranges of melperone and drug quantification in different matrices. Methods An LC-MS/MS method was applied for analyses performed in blood and tissue samples. Quantification based on standard addition and sample preparation on liquid–liquid extraction with 1-chlorobutane. An appropriate tissue homogenization was performed ahead of extraction with an IKA Ultra-Turrax-Tube-Drive®. A Luna 5 µm C18 (2) 100 Å, 150  × 2 mm analytical column was used for chromatographic separation and the elution was performed with two mobile phases consisted of A (H2O/methanol = 95/5, v/v) and B (H2O/methanol = 3/97, v/v) both with 10 mM ammonium acetate and 0.1% acetic acid. Results A multi-drug LC-MS/MS analytical method developed was applied successfully for melperone quantification in different post-mortem matrices. No analytical problems could be identified during method development and analyses of real samples. The melperone lethal concentration calculated in femoral blood of the drug mono-intoxication investigated was 10 mg/L. Melperone concentration distribution was presented for the first time. Conclusions The lethal reference concentration of melperone in femoral blood of 17.1 mg/L pointed out in different reference lists should be used with caution. Instead, a lower lethal melperone concentration should be considered. The post-mortem concentration distribution of the drug presented could be helpful in the interpretation of cases where no blood samples are available.