A patient with COPD is prescribed inhaled ipratropium bromide for bronchodilation. Compared to atropine, ipratropium is preferred in COPD because it:

• A Produces more potent bronchodilation by selectively blocking M1 receptors
• B Stimulates beta-2 receptors simultaneously with muscarinic blockade
• C Is a quaternary ammonium compound with minimal systemic absorption and drying of secretions ✓
• D Selectively blocks M2 autoreceptors, increasing acetylcholine release

Explanation

Ipratropium is a quaternary ammonium derivative of atropine that, when inhaled, has minimal systemic absorption and limited ability to dry bronchial secretions or impair mucociliary clearance, a significant advantage over systemic anticholinergics in COPD patients with viscous sputum. Its bronchodilation comes from non-selective muscarinic blockade, not receptor selectivity.

Reference: Katzung Basic and Clinical Pharmacology, 15th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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