title: Coma from long-term overingestion of isoniazid.
abstract: Overingestion of isoniazid can cause confusion, slurred speech, seizures, coma, and death. Most cases of a central nervous system toxic reaction due to isoniazid use result from sudden intentional or accidental overdose. We describe a patient taking 1200 mg of isoniazid daily for 6 weeks who presented to the hospital with confusion and lethargy that progressed to coma. Within 30 minutes of receiving 1 g of intravenous pyridoxine hydrochloride, the patient was fully alert and lucid. The diagnosis of a toxic reaction to isoniazid was delayed by the possibility of concurrent active neurosyphilis and the failure to initially consider isoniazid poisoning in a patient without a history of sudden isoniazid overdose.
authors.affiliation: Department of Medicine, University of Mississippi School of Medicine, Jackson, USA.
authors.forename: A R
authors.initials: AR
authors.lastname: Salkind
authors.forename: C C
authors.initials: CC
authors.lastname: Hewitt
mesh_terms: D000995:Antitubercular Agents / Q000008:administration & dosage / Q000009:adverse effects*; D003128:Coma / Q000139:chemically induced*; D062787:Drug Overdose / Q000150:complications; D006801:Humans; D007538:Isoniazid / Q000008:administration & dosage / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged
chemical_list: D000995:Antitubercular Agents; D007538:Isoniazid