Which two agents are listed as bronchodilators?

Which two agents are listed as bronchodilators?

• A. Theophylline and Tiotropium bromide
• B. Albuterol and Salmeterol
• C. Ipratropium and Montelukast
• D. Fluticasone and Budesonide

Answer: (A)

Bronchodilators relieve airway constriction by relaxing the smooth muscle of the airways. Theophylline works by inhibiting phosphodiesterase enzymes, which raises intracellular cAMP in airway smooth muscle, leading to relaxation; it also blocks adenosine receptors that can promote constriction. Tiotropium bromide is an antimuscarinic drug that blocks acetylcholine on M3 receptors in the airways, reducing vagal-mediated bronchoconstriction and producing sustained airway dilation. Using these two together shows two distinct, effective mechanisms for bronchodilation: increasing cAMP to relax muscle and blocking parasympathetic constriction. The other options include anti-inflammatory drugs or leukotriene antagonists, which are not bronchodilators themselves, making Theophylline and Tiotropium bromide the correct pairing here.

Bronchodilators relieve airway constriction by relaxing the smooth muscle of the airways. Theophylline works by inhibiting phosphodiesterase enzymes, which raises intracellular cAMP in airway smooth muscle, leading to relaxation; it also blocks adenosine receptors that can promote constriction. Tiotropium bromide is an antimuscarinic drug that blocks acetylcholine on M3 receptors in the airways, reducing vagal-mediated bronchoconstriction and producing sustained airway dilation. Using these two together shows two distinct, effective mechanisms for bronchodilation: increasing cAMP to relax muscle and blocking parasympathetic constriction. The other options include anti-inflammatory drugs or leukotriene antagonists, which are not bronchodilators themselves, making Theophylline and Tiotropium bromide the correct pairing here.