Magnesium and Asthma

Magnesium is sometimes used to treat severe asthma attacks in the emergency department (ED) and hospital settings. It can open up the airway and reduce inflammation. Doctors only use magnesium when quick-relief drugs for asthma have not worked.¹

Regular magnesium dietary supplements may improve asthma control. But there is not much evidence that they are helpful. And too much magnesium can cause side effects. Talk to your doctor before taking magnesium supplements.²

How does magnesium work?

Magnesium is a bronchodilator. This means that it opens up the airway. This makes it easier to breathe air in and out of the lungs. Magnesium also seems to have an anti-inflammatory effect. This can help reduce airway inflammation.³

Because of these effects, experts believe magnesium may be useful in asthma. Magnesium can improve shortness of breath and other symptoms of asthma. It can also make the airways less sensitive to triggers.³

How is magnesium used to treat severe asthma attacks?

Magnesium is used to treat severe asthma attacks in children. It can be injected or infused into the vein. It can also be inhaled through a nebulizer.¹

Magnesium is not the first treatment option for asthma attacks. Doctors use it in life-threatening situations when other treatments have not worked. First, they will try:¹

• Short-acting beta agonists
• Muscarinic antagonists
• Corticosteroids

Magnesium is used to treat asthma attacks in about 10 percent of children in the ED. It is used in about 25 percent of ED visits that result in hospital admission. Doctors only use magnesium late in treatment and in severe cases in children.⁴

Evidence for the benefits of magnesium is mixed. Most large studies have not shown a clear health benefit. However, magnesium may lower the risk of hospital admission for certain people. Experts suggest using magnesium only when needed in children with a severe asthma attack and only in a hospital. They do not recommend regular, unsupervised use.^1,5,6

Do magnesium supplements improve asthma symptoms?

Many people do not get enough magnesium in their diets. Foods that naturally have magnesium in them include:⁷

• Nuts, seeds, and whole grains
• Leafy vegetables
• Milk and yogurt

A few servings of foods that contain a good amount of magnesium can meet your daily needs. Daily supplements can also increase your intake of magnesium.⁷

Magnesium deficiency (levels that are too low) may be more common in people with asthma. It may be even more common in people who have had severe asthma attacks. Some people think magnesium supplements may improve asthma symptoms.⁸

Some small studies have shown that magnesium supplements improve asthma control and quality of life. However, the evidence from these studies does not prove that magnesium works. We need better-designed and larger studies to know more about the use of magnesium supplements for asthma.^2,8

Experts do not recommend regular magnesium supplements for asthma. Too much magnesium can cause:⁷

• Nausea
• Cramping
• Diarrhea
• Unsafe, high magnesium levels

Magnesium can interfere with other medicines. Talk to your doctor before taking any magnesium supplements.⁷