Which of the following best describes the action of anticholinergic agents?

Anticholinergic agents are known to inhibit the action of acetylcholine by blocking its receptors, specifically the muscarinic and sometimes nicotinic receptors in the body. Acetylcholine is a neurotransmitter that mediates various functions in the autonomic nervous system, including muscle contractions and the modulation of glandular secretions. When anticholinergic agents are administered, they prevent acetylcholine from binding to its receptors, thereby reducing its effects. This mechanism is crucial in conditions where the reduction of parasympathetic activity is desired, such as in treating asthma by dilating air passages, or in cases of excessive salivation and motion sickness where decreased secretions are beneficial. Thus, the primary action of these agents is a direct inhibition of acetylcholine’s action, highlighting their therapeutic role in various medical conditions.