Carfentanil related death first encountered in Hong Kong: Two case reports

Abstract Carfentanil is a highly potent fentanyl analogue as well as a new psychoactive substance (NPS) which aroused concerns and research efforts in recent years. In this paper, 2 cases involving carfentanil and the quantitative assay using LC-MS/MS is described. Deceased 1 was a 52-year-old male with carfentanil detected in the peripheral blood at a level of 0.5 ng/mL. Carfentanil was also detected in the gastric content. Deceased 2 was a 25-year-old male with carfentanil detected in iliac blood at a level of 0.9 ng/mL. Without information revealing the potential involvement of carfentanil, screening of gastric content provided crucial information in these cases. Since the carfentanil concentration was very low in the blood, a sensitive LC-MS/MS method for determination of carfentanil in blood is also described.