For instance, your doctor may instruct you to take more medicine than usual if your peak flow drops a certain amount, say 70 percent of normal, or to get medical help right away if it falls to 30 percent of normal. In the past, a vague sense of not feeling well was the only indication a person had that an asthma attack was imminent. Peak-flow meters give you . Such drugs are called bronchodilators. They are sprayed into the mouth and breathed directly into the lungs.
Doctors recommend using the medication from five minutes to an hour before exercise.
If breathing problems develop during exercise, you may need to take another dose. The most common side effect of bronchodilators is feeling jittery, says Otulana. This drug, which is also an inhalant, prevents the lining of the airways from swelling in response to cold air or allergic triggers, explains Otulana, and must be taken on a regular basis for the treatment of asthma. Cromolyn sodium can be used up to 15 minutes before engaging in physical activity. Cromolyn has few side effects, according to Otulana.