Chapter 12: Cholinergic Drugs Affecting The ANS - Prototype Drugs

Question 1

Cholinergic Agents (Parasympathomimetic) Prototype Drug

Answer 1

Bethanechol

Question 2

Bethanechol therapeutic and pharmacological class

Answer 2

• Therapeutic class: Non-obstructive urinary retention drug; Pharmacological class: Muscarinic Cholinergic receptor drug

Question 3

Bethanechol Actions and Uses

Answer 3

• Activates parasympathetic nervous system
• induces rest and digest response
• used for glaucoma, non-obstructive urinary retention, myasthenia Gravis, Alzheimer’s disease
• effects most noted in digestive and urinary tracts

Question 4

Bethanechol Adverse Effects

Answer 4

S - Salivation, sweating
L - lacrimation
U - Urinary frequency
D - diarrhea
G - GI effects
E - emesis
D - decreased HR and BP

Question 5

Bethanechol Admin Alerts

Answer 5

• Route: PO or SubQ (not interchangeable)
• Monitor BP, pulse, and respirations before admin and for atleast 1 hour after subQ admin
• Pregnancy category C

Question 6

bethanechol Contraindications

Answer 6

Contraindicated in patients with:
- Asthma
- Epilepsy
- Parkinsonism
- Hyperthyroidism
- Peptic ulcer disease
- Bradycardia
- Urinary obstructions like BPH
Caution in patients with
- suspected urinary obstruction
- COPD
Extreme caustion in patients with disorders that could be aggravated by increased contractions of the digestive tract
- Suspected obstruction
- Active Ulcer
- Inflammatory disease

Question 7

bethanechol Interactions

Answer 7

• Cholinesterase inhibitors - increased cholinergic effects
• Procainamide, quinidine, atropine, and epinephrine - decreased cholinergic effects

Question 8

bethanechol Lab Tests

Answer 8

May increase serum aspartate aminotransferase (AST), amylase, and lipase

Question 9

bethanechol: treatment of OD

Answer 9

• Atropine sulfate is a specific antidote
• SubQ injection of atropine is preferred except in emergencies when the IV route may be used

Question 10

Cholinergics (parasympathomimetics) Nursing Considerations (bethanechol)

Answer 10

• Monitor liver enzymes
• calculate and monitor doses
• monitor I’s and O’s
• monitor for blurred vision
• monitor for orthostatic hypotension

Question 11

Anticholinergic Agents (parasympatholytics) Prototype drug

Answer 11

Atropine

Question 12

Atropine Therapeutic and pharmacologic class

Answer 12

• Therapeutic class: antidote for anticholinesterase poisoning
• Pharmacologic class: Muscarinic cholinergic receptor blocker

Question 13

Atropine Actions and Uses

Answer 13

• Inhibits the parasympathetic nervous system
• Induces the fight-or flight symptoms

Used for
- Peptic ulcer
- IBS
- Pupil dilation
- Bradycardia
- Preanesthetic - suppress secretions
- Asthma
- hypermotility diseases of the GI tract - IBS

Question 14

Atropine Adverse Effects

Answer 14

Can’t see: dry eyes, photophobia
Can’t Pee: urinary retention
Can’t Spit: dry mouth
Can’t Poop: constipation
- will also see tachycardia, CNS stimulation (may progress to delirium/coma), decreased sweating

Question 15

Atropine Admin Alerts

Answer 15

• Route: IV, IM, PO, SubQ (oral/subQ not interchangeable
• monitor BP, Pulse RR before admin and for at least 1 hr after subQ admin
• pregnancy category C

Question 16

Atropine Contraindications

Answer 16

• Glaucoma: may increase pressure within the eye
• obstructive disorders of the GI Tract, paralytic ileus
• bladder neck obstruction, BPH
• Myasthenia gravis
• Cardiac insufficiency
• acute hemorrhage

Question 17

Atropine Interactions

Answer 17

• increased effects with antihistamines , TCA’s, quinadine, procainamide
• decreased effects of levodopa
• caution with herbal supplements that may increase atropines effects - accidental poisoning with nightshade (children mistake for cherries)

Question 18

Atropine treatment of OD

Answer 18

• OD may cause CNS stimulation or depression
• short acting barbiturate or diazepam (valium) may be administered to control convulsions
• Physostigmine is an antidote for atropine poisoning - quickly reverse the coma caused by large doses of atropine

Question 19

Anticholinergic Nursing Considerations (Atropine)

Answer 19

• Monitor muscle strength and neuromuscular status
• monitor ptosis, diplopia, and chewing
• schedule medications around meal time
• schedule activities to avoid fatigue
• Monitor for muscle weakness
• Monitor for signs of anticholinergic crises
• report changes in HR, BP, or development of dysrhythmias
• Provide conform measures for dry mouth
• minimize exposure to heat or cold or strenuous exercise
• Monitor I’s and O’s
• Monitor patient for abdominal distention, and auscultate for bowel sounds