Biochemical toxicology and suicide in Ireland: a laboratory study

Biochemical toxicology in suicides provides a template to improve preventive interventions in cases of suicide. The menu for biochemical toxicological analysis in coroners' cases is not prescriptive in Ireland or in the United Kingdom. The aim of the study was to confirm that reliance on the results of an immunoassay screen for drugs of abuse and common analgesics in order to select samples for compound confirmation by gas chromatography-mass spectrometry is likely to understate the potential role of drugs in suicide. Blood and urine samples were analyzed using enzyme immunoassay, alcohols by gas chromatography and urines were screened by Bio-Rad's Rapid Emergency Drug Identification (REMEDi) system. Laboratory data from analysis of 132 cases of suicide, including 101 cases of hanging revealed that 83 % were male confirming suicide as a male epidemic. Overall, alcohol was a factor in 57 %, benzodiazepines in 26 %, cannabinoids in 11 %, opioids in 19.7 %, sympathomimetics in 7.5 %, cocaine in 4.5 %, antidepressants 22 %, antipsychotics in 10 %, hypnotics in 5 %, and antihistamines in 4 % of these cases. Screening compounds in cases of hanging and other suicides should extend beyond the narrow focus of alcohol and illicit drugs to include a wide spectrum of psychoactive and other compounds as a standard procedure. The wide range of licit and illicit compounds found in these cases reflects current experience and dictates the necessity for chromatographic screening with mass spectroscopy confirmation in all cases as best practice.