Which COPD drug is a phosphodiesterase inhibitor?

Which COPD drug is a phosphodiesterase inhibitor?

• A. Ipratropium
• B. Theophylline
• C. Budesonide
• D. Salmeterol

Answer: (B)

The drug that fits the phosphodiesterase inhibitor mechanism is theophylline. By inhibiting phosphodiesterase, it prevents the breakdown of cyclic AMP in airway smooth muscle, leading to increased cAMP levels. This causes relaxation of the smooth muscle and bronchodilation, helping to open the airways in COPD. Theophylline also has some anti-inflammatory effects, in part due to its action on adenosine receptors. It’s been used historically for COPD but is now less common because of a narrow therapeutic window and many drug interactions, which is why monitoring blood levels is often required. Among the other options, ipratropium is an antimuscarinic bronchodilator, budesonide is an inhaled corticosteroid, and salmeterol is a long-acting beta-2 agonist.

The drug that fits the phosphodiesterase inhibitor mechanism is theophylline. By inhibiting phosphodiesterase, it prevents the breakdown of cyclic AMP in airway smooth muscle, leading to increased cAMP levels. This causes relaxation of the smooth muscle and bronchodilation, helping to open the airways in COPD. Theophylline also has some anti-inflammatory effects, in part due to its action on adenosine receptors. It’s been used historically for COPD but is now less common because of a narrow therapeutic window and many drug interactions, which is why monitoring blood levels is often required. Among the other options, ipratropium is an antimuscarinic bronchodilator, budesonide is an inhaled corticosteroid, and salmeterol is a long-acting beta-2 agonist.