Pharmacology And Pathophysiology Hypertension, Allergies, Burns, And Hair Disorders Practice Test

Theophylline is a methylxanthine bronchodilator used to help open the airways in asthma and COPD. It works by inhibiting phosphodiesterase, which raises cAMP levels in airway smooth muscle and promotes relaxation, and by blocking adenosine receptors that can promote bronchoconstriction. This combination makes it effective as a bronchodilator in these conditions. It’s distinct from other options: beta-agonists provide rapid bronchodilation by directly stimulating beta-2 receptors; corticosteroids reduce airway inflammation through gene-mediated effects; and leukotriene receptor antagonists block leukotriene signals involved in inflammation and bronchoconstriction. Because of its narrow therapeutic index and potential drug interactions, theophylline is used less often today, but it remains categorized as a methylxanthine bronchodilator for asthma and COPD.