Question

What mechanism underlies the gastrointestinal discomfort induced by macrolides?

• A. Histamine receptor agonist
• B. Adrenergic receptor agonist
• C. Motilin receptor agonist
• D. Binding to 50 S ribosomal subunit

Hint:

Macrolides stimulate motilin receptors → increased GI motility → cramping.

Answer 1

The Correct Option is C

Macrolides (e.g., erythromycin) act as motilin receptor agonists, which increase gastrointestinal motility. This stimulation of gut smooth muscle contributes to the common side effect of GI discomfort.