anticholinergic /-kō′lənur″jik/ [Gk, anti + chole, bile, ergein, to work] , 1. pertaining to a blockade of acetylcholine receptors that results in the inhibition of the transmission of parasympathetic nerve impulses. 2. an anticholinergic agent that functions by competing with the neurotransmitter acetylcholine for its receptor sites at synaptic junctions. Anticholinergics are used to treat spastic disorders of the GI tract, to reduce salivary and bronchial secretions before surgery, or to dilate the pupil. Some anticholinergics reduce parkinsonian symptoms but are never considered primary agents for therapy. Atropine in large doses stimulates the central nervous system and in small doses acts as a depressant. Among numerous cholinergic blocking agents are atropine, belladonna, glycopyrrolate, hyoscyamine, methixene hydrochloride, trihexyphenidyl hydrochloride, and scopolamine. Also called cholinergic blocking agent, parasympatholytic. See also antiadrenergic.
