IV magnesium for children with severe asthma attacks in the emergency department

Magnesium Trial in Acute Asthma in Emergency Department

This trial will test whether a single 30-minute IV magnesium infusion helps children aged 2–17 with moderate–severe asthma after standard ED treatment breathe better and avoid hospital admission.

Quick facts

• Phase: Phase 3
• Study type: Interventional
• Enrollment: 192 (estimated)
• Ages: 2 Years to 17 Years
• Sex: All
• Sponsor: The Hospital for Sick Children (Academic / other)
• Locations: 6 sites (Calgary, Alberta and 5 other locations)
• Trial ID: NCT06785272 on ClinicalTrials.gov

What this trial studies

This is a randomized, double-blind, placebo-controlled trial across six centres comparing IV magnesium sulfate (75 mg/kg, max 2.0 g) to an identical-volume 0.9% saline placebo given as a 30-minute infusion. Eligible children receive the infusion after routine systemic corticosteroids and three inhaled bronchodilator treatments if their PRAM score remains ≥5. Outcomes are recorded during a 180-minute ED observation period and again at 72 hours after ED discharge, with monitoring for hypotension and other adverse effects. The trial aims to address prior inconsistent evidence by using validated clinical scores and standardized timing of the intervention relative to co-therapies.

Who should consider this trial

Good fit: Children aged 2 to 17 with physician-diagnosed asthma who still have moderate–severe symptoms (PRAM ≥5) after three inhaled bronchodilator treatments and routine corticosteroids in the ED.

Not a fit: Children who need airway support on arrival, who received IV magnesium within 24 hours before arrival, or who have milder asthma (PRAM <5) are unlikely to benefit from this intervention.

Why it matters

Potential benefit: If effective, IV magnesium could shorten emergency visits, reduce hospital admissions, and improve breathing for children with moderate–severe acute asthma.

How similar studies have performed: Small early randomized trials suggested fewer hospitalizations with IV magnesium, but larger observational studies have not shown consistent outcome improvements, so the evidence to date is mixed.

Eligibility criteria

Inclusion criteria:

1. Age 2.00-17.99 years (prior to 18th birthday),
2. Diagnosis of asthma, defined as an asthma or probable asthma diagnosis/asthma-like phenotype made by a physician (this includes ED physician) in a patient who in the opinion of the treating ED physician requires therapy for acute asthma in the ED (GINA asthma guidelines, 2024).
3. Moderate-severe asthma after initial therapy with 3 treatments of inhaled salbutamol and ipratropium, defined as an eligibility PRAM ≥5, indicating a strong association with hospitalization.

Exclusion criteria:

1. Receipt of IVMg within 24 hours prior to ED arrival.
2. Need for airway support on arrival. (Airway support on arrival meeting exclusion criteria will include immediate need for high flow nasal cannula therapy, non-invasive CPAP/bi-PAP ventilation or invasive ventilation with endotracheal intubation, as decided by the attending Emergency Department (ED) physician. Supplemental oxygen therapy will not represent an exclusion criterion.)
3. Known renal, chronic pulmonary, neurologic, cardiac or systemic disease: these may influence outcomes after Mg.
4. Known hypersensitivity to Mg sulfate.
5. Previous enrollment.
6. Poor mastery of English and/or French language precluding informed consent understanding.
7. No phone/email; unavailable for follow-up

Where this trial is running

Calgary, Alberta and 5 other locations

• Alberta Children's Hospital — Calgary, Alberta, Canada (Not_yet_recruiting)
• Stollery Children's Hospital — Edmonton, Ontario, Canada (Not_yet_recruiting)
• McMaster Children's Hospital — Hamilton, Ontario, Canada (Not_yet_recruiting)
• Children's Hospital of Eastern Ontario — Ottawa, Ontario, Canada (Not_yet_recruiting)
• The Hospital for Sick Children — Toronto, Ontario, Canada (Recruiting)
• CHU-Sainte Justine Hospital — Montreal, Quebec, Canada (Not_yet_recruiting)

Study contacts

• Principal investigator: Suzanne Schuh, MD — The Hospital for Sick Children
• Study coordinator: Sunita O'Shea

Conditions Asthma; asthma, magnesium sulfate; pediatric, acute asthma