Cholinergic Drugs

Question 1

What do cholinergic drugs stimulate?

Answer 1

Parasympathetic nervous system

Question 2

Nicotinic Receptors

Answer 2

Located in the ganglia of PSNS and SNS

We want to decrease nicotinic reactions

Question 3

Muscarinic Receptors

Answer 3

Located postsynaptically in the effector organs of PSNS

We want to increase muscarinic reactions

Question 4

Cholinergic Drug Effects

Answer 4

Stimulate intestine and bladder
Stimulate pupils
Increase salivation and sweating
Decrease cardiovascular effects
Narrow airways

Question 5

Cholinergic Doses

Answer 5

At recommended doses, cholinergics affect muscarinic receptors.
At high doses, cholinergics stimulate nicotinic receptors (causes undesirable effects)

Question 6

Indirect-Acting Drugs

Answer 6

Used for diagnosis and treatment of myasthenia gravis
Used to reverse neuromuscular blocking drugs
Cause skeletal muscle contractions

Question 7

Contraindications of Cholinergic Drugs

Answer 7

Known drug allergy, GI obstruction, bradycardia, hyperthyroidism, epilepsy, hypotension, COPD, Parkinson’s

Question 8

Adverse Effects

Answer 8

Bradycardia, hypotension, syncope, dizziness, increased secretions, abdominal cramps, bronchospasms

Question 9

Cholinergic Crisis

Answer 9

Circulatory collapse, hypotension, bloody diarrhea, shock, cardiac arrest
SLUDGE

Early signs include abdominal cramps, salivation, skin flushing, nausea, transient syncope, transient complete heart block, dyspnea, orthostatic hypotension

Question 10

Treatment of Cholinergic Crisis

Answer 10

Early phase: atropine

Severe: epinephrine

Question 11

Bethanechol (Urecholine)

Answer 11

Direct-acting cholinergic agonist

Used to help patients urinate again if they have nonobstructive urinary retention

Question 12

Adverse Effects of Bethanechol

Answer 12

Syncope, hypotension with reflex tachycardia, headache, seizure, GI upset, asthma attacks

Question 13

Interactions of Bethanechol

Answer 13

Acetylcholinesterase inhibitors (indirect-acting cholinergics)

Question 14

Donepezil (Aricept)

Answer 14

Cholinesterase inhibitor that increases ACh by inhibiting acetylcholinesterase
Used in treatment of mild to moderate Alzheimer’s
Does not cure the disease

Question 15

Adverse Effects of Donepezil

Answer 15

GI upset, drowsiness, dizziness, insomnia, muscle cramps, bradycardia, syncope, hypertension, hypotension

Question 16

Interactions of Donepezil

Answer 16

Anticholinergics and NSAIDs

Question 17

Pyridostigmine (Mestinone)

Answer 17

Used to treat myasthenia gravis by increasing ACh and inhibiting acetylcholinesterase

Question 18

Edrophonium (Tensilon)

Answer 18

Used to diagnose myasthenia gravis
Helps differentiate between myasthenia gravis and cholinergic crisis
Tensilon test: give IV push Tensilon, patient’s symptoms disappear for a short period of time

Question 19

Nursing Implications

Answer 19

Assess for presence of GI obstructions
Do not stop abruptly
Encourage patients with myasthenia gravis to take medication 30 minutes before eating
Teach that therapeutic effects of anti-Alzheimer’s drugs may not occur for up to 6 weeks
Atropine is the antidote for cholinergics