The drugs consist of two main types. Preventers include inhaled steroids such as Flovent, Pulmicort . Other preventers include inhaled cromolyn and Tilade. Singulair and Accolate are available in tablet form and are also sometimes used to prevent asthma. Relievers are available in different forms: inhalers, tablets or capsules and syrup. They include a group of drugs called beta-agonists like Ventolin HFA. Serevent and Foradil are also beta-agonists with more preventive than relieving actions. Other relievers which can be inhaled include Atrovent HFA . Occasionally theophylline and aminophylline may be used.
Relievers like Ventolin HFA relax the muscles of the air passages, thereby opening them to allow easier breathing. They are short acting and work well when given as a spray, inhaler or mist. They can also be given by tablet or syrup. Some preventers (e.g. Serevent) may also relax the muscles of the air passages. Other preventers such as cromoclycate, Pulmicort and Tilade work to prevent asthma attacks by reducing inflammation of the air passage linings. They are long-acting and may be given as tablets, capsules or by inhalation. They do not work quickly enough to be used as relievers once an asthma attack has occurred.