This report describes a death related to the abuse of and intoxication by mephenesin. To the best of our knowledge, this is the first report case of lethal intoxication involving solely mephenesin and reporting mephenesin blood concentrations. The victim was a 48-year-old woman found unconscious at home. Resuscitation was unsuccessful. Toxicological analysis was performed on a blood sample collected during resuscitation. The results being negative, the body was exhumed for an autopsy, which revealed bronchial inhalation syndrome. Analysis in a second laboratory has revealed the presence of mephenesin in samples collected during autopsy. No other drug/toxin was found, and alcohol was negative. Reanalysis of the peripheral blood collected during resuscitation found a mephenesin concentration of 15.81 microg/mL (15-fold greater that the maximum concentration that would result from a single intake of a 500 mg formulation). The pathologist has concluded on a bronchial inhalation syndrome consecutive to a mephenesin overdose as the cause of death. The manner of this death is discussed in the light of the toxicological hair analysis and the medical past of the victim.