What is bethanechol best described as?

What is bethanechol best described as?

• A. A beta-adrenergic antagonist
• B. A nicotinic receptor blocker
• C. A cholinergic agonist; carbachol with beta-methyl
• D. A muscarinic receptor antagonist

Answer: (C)

Bethanechol is a cholinergic agonist that preferentially activates muscarinic receptors. It’s a synthetic choline ester similar to carbachol but with a beta-methyl group, which reduces nicotinic activity and makes it more resistant to acetylcholinesterase. This gives mainly muscarinic effects, such as increased smooth muscle tone in the gut and bladder, which is why it’s used to treat postoperative ileus and urinary retention. It is not a beta-adrenergic antagonist, not a nicotinic receptor blocker, and not a muscarinic antagonist.

Bethanechol is a cholinergic agonist that preferentially activates muscarinic receptors. It’s a synthetic choline ester similar to carbachol but with a beta-methyl group, which reduces nicotinic activity and makes it more resistant to acetylcholinesterase. This gives mainly muscarinic effects, such as increased smooth muscle tone in the gut and bladder, which is why it’s used to treat postoperative ileus and urinary retention. It is not a beta-adrenergic antagonist, not a nicotinic receptor blocker, and not a muscarinic antagonist.