title: Hypokalemic metabolic acidosis attributed to cough mixture abuse.
abstract: This report describes a patient with mixed normal anion gap hyperchloremic metabolic and respiratory acidosis associated with hypokalemia attributed to cough mixture abuse. Metabolic acidosis was likely related to an overdose of ammonium chloride, whereas respiratory acidosis was probably related to the effect of hypokalemia on respiratory muscles, causing hypoventilation. Hypokalemia was caused by a transcellular shift of potassium induced by ephedrine and pseudoephedrine. Both ammonium chloride and ephedrine were probably present in the cough mixture obtained by our patient as an over-the-counter medication. Physicians should be aware of the potential for cough mixture abuse to cause major electrolyte disturbances that may carry the risk for major cardiac arrhythmias, particularly in youth.
authors.affiliation: Department of Medicine, Renal Unit, Queen Elizabeth Hospital, Hong Kong, SAR. wongfkm@hotmail.com
authors.forename: K M
authors.initials: KM
authors.lastname: Wong
authors.forename: W L
authors.initials: WL
authors.lastname: Chak
authors.forename: C Y
authors.initials: CY
authors.lastname: Cheung
authors.forename: Y H
authors.initials: YH
authors.lastname: Chan
authors.forename: K S
authors.initials: KS
authors.lastname: Choi
authors.forename: K F
authors.initials: KF
authors.lastname: Chau
authors.forename: C S
authors.initials: CS
authors.lastname: Li
mesh_terms: D000138:Acidosis / Q000139:chemically induced*; D000142:Acidosis, Respiratory / Q000139:chemically induced; D000328:Adult; D000643:Ammonium Chloride / Q000506:poisoning*; D000996:Antitussive Agents / Q000506:poisoning*; D062787:Drug Overdose; D006801:Humans; D007008:Hypokalemia / Q000139:chemically induced*; D008297:Male; D018908:Muscle Weakness / Q000139:chemically induced; D004366:Nonprescription Drugs / Q000506:poisoning*; D012132:Respiratory Muscles / Q000187:drug effects; D019966:Substance-Related Disorders / Q000150:complications*
chemical_list: D000996:Antitussive Agents; D004366:Nonprescription Drugs; D000643:Ammonium Chloride