Sympathomimetic toxicity in a case of analytically confirmed recreational use of naphyrone (naphthylpyrovalerone).

CONTEXT: Naphyrone (naphthylpyrovalerone) is a cathinone derivative and recreational drug related to mephedrone. CASE: We report a 31-year-old man who ingested a dose of naphyrone (100 mg), which produced acute sympathomimetic toxicity with restlessness, insomnia, anxiety, and hallucinations lasting for 2 days. Naphyrone was detected in the patient's plasma by gas chromatography with mass spectrometry at concentrations of 0.03 and 0.02 mg/L, 40 and 60 h after drug intake, respectively. DISCUSSION: Based on the present case report and user web-reports, as well as on the chemical structure and pharmacological characteristics, naphyrone produces stimulant-like psychotropic effects and sympathomimetic toxicity.