Copyright © 2011 by Elsevier Inc. All rights reserved. Cholinergic Drugs (p. 313) Also known as cholinergic agonists or parasympathomimetics Mimic effects of the PSNS neurotransmitter acetylcholine (ACh) Cholinergic drugs stimulate the parasympathetic nervous system. Cholinergic drugs, also known as cholinergic agonists, mimic the effects of acetylcholine and are therefore sometimes referred to as parasympathomimetics. These drugs can stimulate cholinergic receptors either directly or indirectly. NURSING APPLICATION: Why would Ms. Jackson be on a cholinergic drug? Copyright © 2011 by Elsevier Inc. All rights reserved.

Indirect-Acting Cholinesterase Inhibitors (p. 314) Reversible Bind to cholinesterase for a period of minutes to hours Irreversible Bind to cholinesterase and form a permanent covalent bond The body must make new cholinesterase to break these bonds Direct-acting cholinergic agonists bind to cholinergic receptors and activate them. NURSING APPLICATION: Ms. Jackson has urinary retention. Would an indirect-acting cholinesterase inhibitor help? Why or why not? Copyright © 2011 by Elsevier Inc. All rights reserved.

Drug Effects (p. 315) SLUDGE acronym Salivation Lacrimation Urinary incontinence Diarrhea Gastrointestinal cramps Emesis Pupils constrict, and intraocular pressure is reduced. At recommended doses, cholinergics affect primarily muscarinic receptors. At high doses, cholinergics stimulate nicotinic receptors. Stimulation of nicotinic receptors causes many undesirable effects. There are many mnemonics to aid in remembering these effects. One is to think of the parasympathetic nervous system as the “rest and digest” system, in contrast to the “flight or fight” sympathetic nervous system. NURSING APPLICATION: How will a direct-acting cholinergic agonist drug help Ms. Jackson’s urine retention? Copyright line.

Nursing Implications (p. 317) Note that these drugs will stimulate the parasympathetic nervous system (PSNS) and mimic the action of ACh Assess for allergies, presence of GI or GU obstructions, asthma, peptic ulcer disease, or coronary artery disease Perform baseline assessment of vital signs and systems overview Atropine is the antidote for cholinergics, and it should be available in the patient’s room for immediate use if needed. NURSING APPLICATION: After assessment for effects of a cholinergic medication, what nursing diagnosis would be appropriate for Ms. Jackson? Copyright © 2011 by Elsevier Inc. All rights reserved.

Drug Effects of Cholenergic-Blocking Drugs (p. 322) Cardiovascular Small doses: decrease heart rate Large doses: increase heart rate CNS Small doses: decrease muscle rigidity and tremors Large doses: drowsiness, disorientation, hallucinations Block or inhibit the actions of acetylcholine in the parasympathetic nervous system Also dilate pupils, decrease GI motility Beneficial in treating exercise-induced bronchospasms, chronic bronchitis, asthma, and chronic obstructive pulmonary disease. NURSING APPLICATION: Why would small doses decrease heart rate and large doses increase heart rate? Why wouldn’t large doses cause the heart rate to become even slower? Copyright © 2011 by Elsevier Inc. All rights reserved.

Copyright © 2011 by Elsevier Inc. All rights reserved. Interactions (p. 324) Antihistamines, phenothiazines, tricyclic antidepressants, MAOIs When given with cholinergic blocking drugs, cause additive cholinergic effects, resulting in increased effects Reduced antipsychotic effects of phenothiazines when taken with anticholinergic drugs Cholinergic blockers have the therapeutic effect of decreasing muscle rigidity and diminishing tremors. NURSING APPLICATION: What symptoms would indicate that an unfavorable interaction has occurred? Copyright © 2011 by Elsevier Inc. All rights reserved.

Nursing Implications (p. 328) Keep in mind that these drugs block the action of ACh in the PSNS Assess for allergies, presence of BPH, glaucoma, tachycardia, MI, HF, hiatal hernia, and GI or GU obstruction Perform baseline assessment of vital signs and systems overview Pediatric and elderly patients have increased susceptibility to the adverse effects of confusion, delirium, constipation, blurred vision, and tachycardia. NURSING APPLICATION: What patient teaching should be provided to a person who is taking a cholinergic-blocking medication? Copyright line.

Nursing Implications (cont’d) (p. 327) Patients may experience sensitivity to light and may want to wear dark glasses or sunglasses When giving ophthalmic solutions, apply pressure to the inner canthus to prevent systemic absorption Antidote for atropine overdose is physostigmine. NURSING APPLICATION: What are symptoms of atropine overdose? Copyright © 2011 by Elsevier Inc. All rights reserved.

Nursing Implications (cont’d) (p. 328) Monitor for therapeutic effects For patients with Parkinson’s disease: fewer tremors and decreased salivation and drooling For patients with urologic problems: improved urinary patterns, less hypermotility, increased time between voiding Monitor for adverse effects Emphasize the importance of adequate fluid and salt intake. NURSING APPLICATION: Why is fluid and salt intake important for Ms. Jackson? Copyright © 2011 by Elsevier Inc. All rights reserved.