EFFECT OF PARENTERAL MAGNESIUM-SULFATE ON PULMONARY FUNCTIONS IN BRONCHIAL-ASTHMA

Eighteen patients with bronchial asthma were studied in a single-blind fashion. Each patient received an infusion of magnesium sulfate (MgSO 4.7H2O 50% W/V) in a dose equivalent to 10 mmol of elemental magnesium . The airways resistance showed a significant decrease (p < 0.01) whil e SGaw increased significantly (p < 0.001) with MgSO4 infusion. FEV1 ( p < 0.01), FEF25-75% (p < 0.05), and V50 (p < 0.05) also showed statis tically significant increase (p < 0.001) with MgSO4 infusion. Signific ant changes in Raw (p < 0.01) and SGaw (p < 0.01) persisted at 10 and 20 min following MgSO4 infusion. No significant side effects were obse rved with MgSO4 infusion. It is concluded that modest improvement in a irways resistance and specific conductance and only small improvement in maximal expiratory flow rates is consistent with a predominant effe ct of MgSO4 on large airways in patients with bronchial asthma.