Antiasthmatics drugs are used for the treatment of asthma. They may be useful either in the treatment or prevention of asthma attacks. Antiasthmatics include adrenergics, anticholinergics, corticosteroids, leukotriene antagonists, mast cell stabilizers, and xanthines along with their uses, dosages, and side effects. Adrenergics include albuterol or salbutamol, bambuterol, epinephrine or adrenaline, formoterol, levosalbutamol, salmeterol, and terbutaline. Anticholinergics include ipratropium and tiotropium. Leukotriene antagonists include montelukast, zafirlukast, and zileuton. Uses, dosages, and side effects of all these drugs are also discussed in this chapter.