Respiratory System ( pharmacology )

Bronchodilators: β₂ agonists (albuterol, salmeterol), antimuscarinics (ipratropium, tiotropium), methylxanthines (theophylline)

Anti-inflammatory drugs: corticosteroids, leukotriene modifiers (montelukast, zileuton), mast cell stabilizers (cromolyn)

Antihistamines: 1st and 2nd generation (diphenhydramine, loratadine)

Antitussives & expectorants: codeine, dextromethorphan, guaifenesin

Oxygen therapy & pulmonary hypertension drugs: sildenafil, bosentan