A blue asthma inhaler is typically used for quick relief of asthma symptoms. These inhalers contain a short-acting beta-agonist (SABA) medication, such as albuterol (salbutamol) or levalbuterol, which works by relaxing the muscles around the airways. This helps to open up the airways and makes it easier to breathe.

Blue inhalers are often called "rescue" or "reliever" because they provide fast relief during an asthma attack or when symptoms suddenly worsen. They are usually used as needed rather than on a regular schedule.