What medication has been shown to be most effective for use before exercise in a child with intermittent asthma?

The most effective medication for use before exercise in a child with intermittent asthma is budesonide/formoterol. This combination provides both a quick relief of symptoms through the formoterol component, which is a long-acting beta-agonist (LABA), and a controller medication through the budesonide, which is a corticosteroid.

When used before exercise, budesonide/formoterol can help prevent exercise-induced bronchoconstriction, allowing the child to engage in physical activities with a decreased risk of asthma symptoms. The rapid onset of action of formoterol makes it particularly beneficial in this setting, while the corticosteroid component helps with overall asthma control.

While other options like albuterol and levalbuterol (both short-acting beta-agonists) are also effective for quick relief of asthma symptoms, they are not combined with a long-term controller like budesonide in this scenario. Montelukast, on the other hand, is a leukotriene receptor antagonist that can be effective for long-term control but does not have the immediate bronchodilator effect needed right before exercise. Therefore, budesonide/formoterol stands out as the optimal choice for pre-exercise use in children with intermittent asthma.