An intravenous solution of magnesium sulphate may be the best way to treat patients suffering from acute asthma attacks. That's the conclusion of two recent meta analyses.
One included seven randomised trials and 668 patients. Magnesium was associated with a significantly lower rate of hospital admissions for patients with severe asthma, but not for those with moderate asthma. Patients with severe asthma who received magnesium also showed significant improvement in breathing and lung capacity (Ann Emerg Med, 2000; 36: 181-90).
The other meta analysis was of nine trials of intravenous magnesium (including the seven in the previous study), and used a different method of analysis and different endpoints. They found a 16 per cent improvement in airway function with magnesium compared with a placebo (Ann Emerg Med, 2000; 36: 191-7).