title: Bronchodilating effect of intravenous magnesium sulfate in bronchial asthma.
abstract: The bronchodilating effect of magnesium sulfate (MgSO4) was studied in ten asthmatic patients with mild attacks. In five patients, 0.5 mmol/min of MgSO4 was administered intravenously for 20 minutes, and the time courses of respiratory resistance, forced vital capacity, and forced expiratory volume at 1 s were studied. In another five patients, MgSO4 dose-response curves were obtained. Soon after administration began, MgSO4 relieved bronchoconstriction in a dose-dependent manner. Maximum responses (mean +/- SE) of respiratory resistance, forced vital capacity, and forced expiratory volume were 71% +/- 3%, 117% +/- 5%, and 118% +/- 1% of initial values, respectively, and were similar to the effects of additional albuterol inhalation. The infusion of MgSO4 also improved dyspnea and piping rales in three other asthmatic patients with a severe attack. We conclude that intravenous infusion of MgSO4 produces a rapid and marked bronchodilation in both mild and severe asthma and may be a unique bronchodilating agent.
mesh_terms: D000328:Adult; D000403:Airway Resistance / Q000187:drug effects; D001249:Asthma / Q000188:drug therapy* / Q000503:physiopathology; D001993:Bronchodilator Agents / Q000627:therapeutic use*; D004305:Dose-Response Relationship, Drug; D004341:Drug Evaluation; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D007262:Infusions, Intravenous; D008278:Magnesium Sulfate / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D014797:Vital Capacity / Q000187:drug effects
chemical_list: D001993:Bronchodilator Agents; D008278:Magnesium Sulfate