SAMA (Short-Acting Muscarinic Antagonists) Bronchodilator Pharmacology

This Is Why with Dr. Busti · Jan 27, 2026 · 24m

Short-acting muscarinic antagonists (SAMAs) are a core bronchodilator drug class you’ll see constantly in COPD care. In this lecture from This is Why, Dr. Busti will learn about short-acting muscarinic antagonists (SAMAs) are a core bronchodilator drug class you’ll see constantly in COPD care—and on exams like the NCLEX. In this lecture, you’ll learn exactly how SAMAs work, when to use them, and what safety pearls can help you avoid common clinical pitfalls in COPD.

You’ll learn how to:

Mechanism of action: muscarinic (M3) blockade → decreased bronchoconstriction

Key drug: ipratropium…