muscarinic receptor antagonist

A muscarinic receptor antagonist is a type of drug that blocks the actions of acetylcholine at muscarinic receptors. Acetylcholine is a neurotransmitter crucial for the parasympathetic nervous system, which controls functions like smooth muscle contraction, blood vessel dilation, and heart rate.

Drugs like atropine and scopolamine are examples of muscarinic receptor antagonists. They suppress parasympathetic actions, leading to reduced bodily secretions (saliva, tears, sweat), relaxation of smooth muscles in the intestines and bladder, increased heart rate, and pupil dilation. These drugs are used in anesthesia to dry secretions and open airways, and in eye exams to dilate pupils. Scopolamine also helps treat motion sickness by affecting the central nervous system.1