Question

Mirabegron is used in the management of overactive bladder

• A. Beta 2 agonist
• B. Beta 3 agonist
• C. M3 antagonist
• D. Beta 1 agonist

Hint:

Beta-3 agonists like mirabegron are preferred in patients who cannot tolerate antimuscarinic side effects for overactive bladder.

Answer 1

The Correct Option is B

Mirabegron is a selective Beta-3 adrenergic receptor agonist primarily used in the treatment of overactive bladder (OAB). Activation of Beta-3 receptors in the detrusor muscle of the bladder leads to relaxation during the storage phase of the urinary bladder cycle, thereby increasing bladder capacity and reducing symptoms of urgency and frequency.
Unlike antimuscarinic agents (such as M3 antagonists), which inhibit bladder contractions by blocking muscarinic receptors, mirabegron works by a different mechanism and generally has a more favorable side effect profile, especially regarding dry mouth and constipation.