Parasympatholytic agents

Atropiae (41), isolated from the deadly nightshade Airopa belladonna L.) is the racemic form, as isolated, of (—)-hyoscyamine [which is not isolated, of course, from the same plant but is typically found ia solanaceous plants such as henbane (HyosQiamus mgerl. )]. Atropiae is used to dilate the pupil of the eye ia ocular inflammations and is available both as a parasympatholytic agent for relaxation of the intestinal tract and to suppress secretions of the saUvary, gastric, and respiratory tracts. In conjunction with other agents it is used as part of an antidote mixture for organophosphorus poisons (see Chemicals in war). 

Pharmacology Ipratropium for oral inhalation is an anticholinergic (parasympatholytic) agent that appears to inhibit vagally mediated reflexes by antagonizing the action of acetylcholine. The bronchodilation following inhalation is primarily a local, site-specific effect, not a systemic one. 

Figure 8-2 Mydriasis induced by 2.5% and 10% phenylephrine (w = 112 eyes). (Reprinted with permission from Paggiarino DA, Brancato LJ, Newton RE. The effect on pupil size and accommodation of sympathetic and parasympatholytic agents. Ann Ophthalmol 1993 25 244-253.)...

Paggiarino DA, Brancato LJ, Newton RE. The effect on pupil size and accommodation of sympathetic and parasympatholytic agents.Ann Ophthalmol 1993 25 244-253. 

The elassic parasympatholytic agent is atropine, and thus anticholinergic drugs used to be referred to as atropinic agents. Typical ef-... 

Parasympatholytic agents (e.g., atropine, the belladonna alkaloids) cause hyposecretion and hypomotility (atony). These agents have been used to treat diarrhea. 

Parasympatholytic agent used against parkinsonism. Anticholinergic. Cryst. Mp 53-55°. 

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