Cholinergic Blocking Drugs

Cholinergic blocking dragp inhibit die activity of acetylcholine in parasympadietic nerve fibers (see Chap. 24 for a description of die role of acetylcholine in the transmission of nerve impulses across parasympadietic nerve fibers). When die activity of acetylcholine is inhibited, nerve impulses traveling along parasympadietic nerve fibers cannot pass from die nerve fiber to die effector organ or structure  

Because of die wide distribution of parasympadietic nerves, tiiese drugs affect many organs and structures of die body, including the eyes, die respiratory and gastrointestinal tracts, the heart, and the bladder (see Display 25-1). 

Cholinergic blocking drugs produce the following responses  

Central nervous sysfe/n-dreamless sleep, drowsiness atropine may produce mild stimulation in some patients e-mydriasis (dilatation of the pupil), cydoplegia (paralysis of accommodation or inability to focus the eye) 

Respiratory frarf—drying of the secretions of the mouth, nose, throat, bronchi, relaxation of smooth muscles of the bronchi resulting in slight bronchodilatation 

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Discuss the uses, general drug actions, general adverse reactions, contraindications, precautions, and interactions of the cholinergic blocking drugs. 

Discuss important preadministration and ongoing assessment activities the nurse should perform on the patient taking cholinergic blocking drugs. 

Discuss ways to promote an optimal response to therapy, how to manage common adverse reactions, and important points to keep in mind when educating patients taking a cholinergic blocking drug. 

However, responses to administration of a cholinergic blocking drug vary and often depend on the drug and the dose used. For example, scopolamine may occasionally cause excitement, delirium, and restlessness. This reaction is thought to be a drug idiosyncrasy (an unexpected or unusual drug effect). 

Other adverse reactions tiiat may be seen with die administration of a cholinergic blocking drug include ... 

SUM MARY DRUG TABLE CHOLINERGIC BLOCKING DRUGS... 

The Patient Receiving a Cholinergic Blocking Drug ASSESSMENT... 

When administering a cholinergic blocking drug, the daily ongoing assessment requires that the nurse closely observes the patient. The nurse checks vital signs,... 

The nurse observesthe elderly patient receiving a cholinergic blocking drug at frequent intervals for excitement, agitation, mental confusion, drowsiness urinary retention, or other adverse effects. If any of these should occur, it is important to withhold the next dose of the drug and contact the primary health care provider. The nurse ensures patient safety until these adverse reactions disappear. 

Cholinergic blocking drugs are usually not included in the preoperative drugs of patients older than 60 years because of the effects of these drugs on the eye and the central nervous ystem. 

One of the most common adverse effects occurring with the use ot cholinergic blocking drugs is a dry mouth. The nurse otters the tollowing suggestions to the patient to help combat this problem ... 

When a cholinergic blocking drug is prescribed for outpatient use, die nurse informs die patient about die more common adverse reactions associated with tiiese drugp, such as dry mouth, drowsiness, dizziness, and... 

Some of die adverse reactions associated widi die cholinergic blocking drugs may be uncomfortable or distressing. The nurse encourages the patient to discuss these problems with die primary healdi care provider. The nurse makes suggestions to lessen the intensity of some of these adverse reactions. 

Mr. Anthony is prescribed a cholinergic blocking drug for the treatment of peptic ulcer. In planning patient teaching for Mr. A nthony before dismissal from the hospital, determine what information must be included to prevent complications of therapy. 

Anticholinergics (cholinergic blocking drug) reduce gastric motility and decrease the amount of acid secreted by the stomach (see Chap. 25). Examples of anticholinergics used for GI disorders include propantheline (Pro-Banthine) and glycopyrrolate (Robinul). 

Haley, T.J., Rhodes, B.M. 1953 Influence of Peripheral Cholinergic Blocking Drugs on Survival Time in X-ray Irradiated Mice. Science 117 139-140. 

Meyers, B. and Domino, E. F. (1964) The effect of cholinergic blocking drugs on spontaneous alternation in rats. Arch. int. Pharmacodyn., 150, 525-529. 

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