Gabapentin, a GABA analogue, is a drug with anticonvulsant properties, used to treat epilepsy in adults and to relieve pain in patients suffering from postherpetic neuralgia. The usual oral daily dose is 300-1800mg, but may be increased to a maximum of 3600mg in 1-3 divided doses. The most reported adverse effects of gabapentin are somnolence, dizziness, ataxia, fatigue and impaired vision. The drug is often associated with opiates in the addict population. A 58-year-old man was found dead at his home. He was treated by gabapentin since 3 years for major neuropathic pain and a depressive syndrome. Body examination did not reveal traumatic injury. Following an initial screening of peripheral blood, all the biological specimens collected during autopsy were analysed, using a dedicated liquid chromatography-tandem mass spectrometry method for gabapentin. Analyses revealed intoxication with gabapentin, including cardiac blood concentration at 33800μg/L, peripheral blood at 42800μg/L and urine at 854200μg/L. Hair (2cm, brown) tested positive at 421pg/mg. The toxicological significance of the measured concentration was difficult to establish because of the limited identification of gabapentin in human hair. These results appear to be compatible with an overdose of gabapentin and the pathologist attributed the death to a fatal intoxication.