Prospective Observational Study of Clinical Outcomes After Intravenous Magnesium for Moderate and Severe Acute Asthma Exacerbations in Children

J Allergy Clin Immunol Pract. 2022 May;10(5):1238-1246. doi: 10.1016/j.jaip.2021.11.028. Epub 2021 Dec 13.


Background: There is limited knowledge regarding whether intravenous magnesium (IV-Mg) improves outcomes in children with acute asthma exacerbations.

Objective: To examine whether IV-Mg improves outcomes in children with moderate and severe exacerbations.

Methods: We performed a secondary analysis using data from a prospective observational cohort of children aged 5 to 17 years with moderate and severe exacerbations. Standardized treatment included systemic corticosteroid and inhaled albuterol, with consideration of IV-Mg (75 mg/kg) for patients with insufficient response after 20 minutes. Propensity score (PS) models were used to examine associations of IV-Mg treatment with change in the validated Acute Asthma Intensity Research Score, hospitalization rate, and time to spacing of inhaled albuterol of 4 hours or more among hospitalized participants.

Results: Among 301 children, median (interquartile range) age was 8.1 (6.4-10.2) years, 170 were Black (57%), 201 were male (67%), and 84 received IV-Mg (28%). In a PS covariate-adjusted multivariable linear regression model, IV-Mg treatment was associated with a 2-hour increase in the Acute Asthma Intensity Research Score (β-coefficient = 0.98; 95% confidence interval [CI], 0.20-1.77), indicating increased exacerbation severity. Three additional PS-based models yielded similar results. Participants receiving IV-Mg had 5.8-fold (95% CI, 2.8-11.9) and 6.8-fold (95% CI, 3.6-12.9) greater odds of hospitalization in PS-based multivariable regression models. Among hospitalized participants, there was no difference in time to albuterol of every 4 hours or more in a PS covariate-adjusted Cox proportional hazards model (hazard ratio = 1.2; 95% CI, 0.8-1.8).

Conclusions: Among children with moderate and severe exacerbations, IV-Mg is associated with increased exacerbation severity, increased risk for hospitalization, and no acceleration in exacerbation resolution among hospitalized participants.

Keywords: Acute asthma exacerbation; Children; IV magnesium.

Publication types

  • Observational Study
  • Research Support, N.I.H., Extramural

MeSH terms

  • Acute Disease
  • Albuterol / therapeutic use
  • Anti-Asthmatic Agents* / therapeutic use
  • Asthma* / chemically induced
  • Asthma* / drug therapy
  • Child
  • Drug Therapy, Combination
  • Female
  • Hospitalization
  • Humans
  • Magnesium / therapeutic use
  • Male


  • Anti-Asthmatic Agents
  • Magnesium
  • Albuterol