Ethchlorvynol ingestion: interpretation of blood concentrations and clinical findings.

Thirty-eight patients who ingested ethchlorvynol were seen at our institution over an 8.7 year period. Eleven involved ethchlorvynol alone ("pure") while the remainder included at least one other drug ("mixed"). Twenty-three of the patients were women. Six patients required hospitalization. Five patients were chronic users of the drug. Admission ethchlorvynol blood concentrations ranged from 3 to 46 mg/L ("pure") and from 3 to 75 mg/L ("mixed"). For the "pure" cases the most common physical findings were depressed level of consciousness (10 cases), dysarthria (7), mydriasis (6), nystagmus (6), areflexia (4), tachycardia (4), and hypotension, ataxia, and respiratory depression (2 cases each). Following "pure" ingestion, ethchlorvynol concentrations greater than 19 mg/L were usually associated with dysarthria, mydriasis, nystagmus, and tachycardia. When concentrations exceeded 38 mg/L, coma, areflexia, hypotension, and respiratory depression were generally noted as well. All patients recovered with supportive care alone.