Chapter 20

Question 1

Cholinergic drugs are also known as ______ or _______

Answer 1

cholinergic agonists; parasympathomimetics

Question 2

What do cholinergic drugs mimic

Answer 2

PSNS neurotransmitter ACh

Question 3

PSNS is “flight or fight” or “rest and digest”

Answer 3

rest and digest; SNS is fight or flight

…they’re opposites.

Question 4

Cholinergic drugs stimulate which system

Answer 4

PSNS

Question 5

What are cholinergic effects (SLUDGE)

Answer 5

increased Salivation
Lacrimation
Urination
Diarrhea
increased GI motility
possible Emesis

Question 6

How do direct-acting cholinergic agonists work?

Answer 6

Bind directly to cholinergic receptors and activate them

Question 7

How do indirect-acting cholinergic agonists work? (Long)

Answer 7

stimulate the postsynaptic release of ACh at the receptor site. This then allows ACh to bind to and stimulate the receptor. Inhibit the enzyme acetylcholinesterase, which breaks down ACh -> more ACh available at the receptors

Question 8

What are the two types of receptors:

Answer 8

Nicotinic and Muscarinic

Question 9

Where are Nicotinic receptors; how do they get their name

Answer 9

located in ganglia of PSNS and SNS; can be stimulated by alkaloid nicotine found in tobacco plant

Question 10

Where are muscarinic receptors; how do they get their name

Answer 10

located postsynaptically in effector organs of PSNS (sm. mu., cardiac muscle, glands); can be stimualted by the alkaloid muscarine isolated form mushrooms

Question 11

What are the 2 mechanisms of action for cholinergic agonists?

Answer 11

Direct-acting vs. indirect-acting

Question 12

How do Indirect-acting (cholinesterase Inhibitors) bind to cholinesterase? (2 ways)

Answer 12

Reversible: bind to cholinesterase for minutes to hours

Irreversible: bind to cholinesterase and form a permanent covalent bond; body must make new cholinesterase in order to break these bonds

Question 13

What are drug effects of cholinergic drugs? (simple)

Answer 13

Stimulate: intestine, bladder, pupils
Increases: salivation, sweating
Cardiovascular effects
Respiratory effects

Question 14

Drug effects of cholinergic drugs (have fun with this one)

Answer 14

Stimulate intestine/bladder:
+ gastric secretions
+ GI motility
+ urniary freq.

Stimulate pupils:
mydriasis
-intraocular pressure

+salivation/sweating

Cardiovascular effects:
- HR
vasodilation

Respiratory effects:
bronchial constriction

• • means increase, - means decrease/reduced

Question 15

What receptors do cholinergics affect at recommended vs. high doses? Which are desirable?

Answer 15

recommended doses: affect muscarinic receptors *desirable

high doses: stimulate nicotinic receptors *undesirable

Question 16

Indications of direct-acting drugs

Answer 16

• intraocular pressure

useful for glaucoma/intraocular surgery, topical application (eyedrops)

Bethanechol (drug name)
+tone/motility of bladder/GI tract, relaxes sphincters -> allows it to empty
usually oral dose or SQ injection

Question 17

Indications of indirect-acting drugs

Answer 17

cause sk. mu. contractions
used for diagnosis/treatment of myasthenia gravis
reverses neuromuscular blocking drugs and anticholinergic poisoning (antidote, physostigmine)

*Donepezil (Aricept): treats mild to moderate alzheimer’s

Memantine/Namenda: not cholinergic, also treats alzheimers blocks stimulation at NMDA receptors (reduces symptoms)

Question 18

What results in adverse effects?

Answer 18

Overstimulation of the PSNS

Question 19

5 systems, and specifics, of adverse effects

Answer 19

Cardiovascular: bradycardia, hypotension, conduction abnormalities (AV block and cardiac arrest)

CNS: h/a, dizziness, convulsions

GI: ab cramps, +secretions, nau, vom

Respiratory: +bronchial secretions, bronchospasms

Other: Lacrimation, sweating, salivation, loss of binocular accommodation,

Question 20

When cholinergic drugs interact with anticholinergics, antihistamines, and sympathomimetics, what happens?

Answer 20

antagonize cholinergic drugs = decreased responses

Question 21

when cholinergic drugs interact with other cholinergic drugs, what happens?

Answer 21

additive effects?

ex. instead of 1+1=2, 1+1=6

Question 22

3 common uses of Gingko

Answer 22

1. organic brain syndrome
2. vertigo
3. tinnitus

Question 23

Adverse effects of Gingko

Answer 23

GI upset, h/a, bleeding, allergic skin reactions

h/a:headache

Question 24

Drug interactions of Gingko

Answer 24

aspirin, NSAIDs, anticoagulants, anticonvulsants, others

Question 25

Cholinergic drugs stimulate the _______ and mimic the action of _____

Answer 25

PSNS; ACh

Question 26

3 things to teach pt’s taking cholinergic drugs:

Answer 26

1. take as ordered, do not abruptly stop
2. change positions slowly (prevent dizzinezz/fainting)
3. overdosing can cause life-threatening symptoms, do not adjust dosages unless directed by a physician

Question 27

What is the antidote for cholinergics, and where should it be kept?

Answer 27

Atropine; should be available in the pt’s room for immediate use if needed

Question 28

Which pt’s need to take medication 30 minutes prior to eating and why?

Answer 28

pt’s with myasthenia gravis; help improve chewing and swallowing

Question 29

2 important things to tell those receiving alzheimer’s meds

Answer 29

1. drugs are for management of symptoms, it is not a cure

2. therapeutic effects may not occur for 6 weeks

Question 30

When monitoring for therapeutic effects, what’re you looking for in:

1. pt’s with myasthenia gravis
2. postoperative pts with decreased GI peristalsis
3. pt’s with urinary retention/hypotonic bladder

Answer 30

1. alleviated s/s of myasthenia gravis
2. increased bowel sounds; passage of flatus; occurrence of bowel movements
3. urination should occur within 60 minutes of bethanechol administration