Beta Blockers USMLE Step 1 Practice Question
A 68-year-old former smoker with COPD presents with persistent dyspnea (RR 22, SpO2 88% on room air). He denies chest pain or palpitations. His current medications include albuterol and inhaled corticosteroids. Chest X-ray shows hyperinflation without acute infiltrates. Laboratory studies reveal normal troponin. He is prescribed an inhaled medication that blocks M3 receptors in the airways, reducing vagally mediated bronchoconstriction and decreasing mucus secretion. Which of the following drugs was most likely prescribed?
Answer choices
- AAlbuterol
- BIpratropiumCorrect answer
- COmalizumab
- DTheophylline
- EMontelukast
- FTiotropium, a long-acting muscarinic antagonist
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