Brian Waters
Fukuoka University, Japan
Title: Tissue distribution of suvorexant in three postmortem cases
Biography
Biography: Brian Waters
Abstract
Statement of the Problem: Suvorexant (Belsomra®) is a relatively new insomnia medication that has been available in the US and Japan since 2014. It is a dual orexin receptor antagonist that promotes sleep by inhibiting the binding of orexin neurons to the OX1R and OX2R receptors. In this report, we describe the detection and quantitation of suvorexant from the postmortem specimens of three recent autopsy cases handled by our department.
Methodology & Theoretical Orientation: Suvorexant was identified by fast GC-MS during routine screening (Fig. 1) and quantitated by a fully validated LC-MS/MS method. Quantitation was achieved by positive electrospray ionization in the selected reaction monitoring mode. Monitored transitions were m/z 451 > 186 for quantitation and m/z 451 > 104 for qualification. Diazepam-d5 was used as an internal standard.
Findings: Suvorexant was detected and quantitated in the body fluids and tissues of three autopsy cases. The specimens included cardiac blood, peripheral blood, urine, liver, kidney, spleen, pancreas, lung, muscle, fat, and cerebrospinal fluid. Tissue distribution across the three cases will be presented and discussed.
Conclusion & Significance: The use of suvorexant as an insomnia medication has recently increased around the world. To our knowledge this is the first instance of suvorexant being quantitated from actual autopsy cases. It is possible the presence of this medication in clinical and forensic samples has been missed due to its high boiling point and thus late elution in gas chromatography. We were able to detect suvorexant in three cases by using fast GC-MS, which significantly reduced its retention time. It is likely that this compound will be encountered more often by the forensic and clinical toxicology communities going forward.