The history and toxicological findings of a suicidal case involving injection of a veterinarian barbiturate euthanasia agent (Vetanarcol containing pentobarbital are presented. Blood pentobarbital concentrations compatible with drug overdose were determined. Almost identical levels were found in blood, cerebrospinal fluid (CSF) and vitreous humour (VH). The highest concentration was measured in the bile. The present case is compared with similar rare cases in the literature.