Cholinergic Drugs

Question 1

What are the classes of direct-acting drugs?

Answer 1

Choline esters or non-ester alkaloids

Question 2

Why is ACh a bad drug of choice?

Answer 2

Rapidly hydrolyzed by plasma AChE, broad effects on nicotinic and muscarinic receptors, and lasts 15-20 secs

Question 3

What are some ways that choline can be modified for longer lasting effects?

Answer 3

beta-methyl group - reduces potency on nicotinic receptors, slows degradation

carbamate group - increases resistance to cholinesterase

Question 4

What property is important about quaternary ammonium groups?

Answer 4

Insoluble in lipids, poorly absorbed, and don’t enter the CNS

Question 5

What are the uses and major side effects of bethanechol?

Answer 5

USE: postoperative/neurogenic ileus, urinary retention

SE: SLUDGE

Question 6

What is the use and major side effects of pilocarpine? What other drug is closely related?

Answer 6

USE: Glaucoma

SE: SLUDGE

Closely related to muscarine

Question 7

What is the use and side effects of cevimeline?

Answer 7

USE: dry mouth (relatively specific for M3 receptors)

SE: SLUDGE

Question 8

What is the use of nicotine replacement therapy?

Answer 8

Smoking cessation

Question 9

Muscarine, pilocarpine, cevimeline, and nicotine are all what class of molecule? What is unique about this class (when compared to bethanecol, for example)?

Answer 9

Non-ester alkaloids; not degraded by AChE

Question 10

Activating the muscarinic receptors of endothelial cells causes ___ release and the ultimate effect is ____.

Answer 10

1) EDRF (NO)

2) relaxation of vascular smooth muscle that has been contracted with NE

Question 11

How do indirect acting cholinergic drugs work?

Answer 11

AChE inhibitors! Keeps naturally released ACh around in the synaptic terminal for longer

Question 12

What is the use and side effects of neostigmine (an AChEI)?

Answer 12

USE: postop/neurogenic ileus, urinary retention, myasthenia gravis, reversal of neuromuscular blockade

SE: SLUDGE, general increase in cholinergic neurotransmission, paralysis

Question 13

What is the use and side effects of physostigmine (an AChEI)?

Answer 13

USE: Glaucoma

SE: SLUDGE, general increase in cholinergic neurotransmission, paralysis

Question 14

What is the use and side effects of donepezil (an AChEI)?

Answer 14

USE: Alzheimer’s

SE: SLUDGE, general increase in cholinergic neurotransmission, paralysis

Question 15

What is the use and side effects of edrophonium (an AChEI)?

Answer 15

USE: Myasthenia gravis (detecting deficiency vs. ACh crisis during weakness), ileus

SE: SLUDGE, general increase in cholinergic neurotransmission, paralysis

Question 16

What is the use and side effects of echothiophate (an AChEI)?

Answer 16

USE: glaucoma

SE: SLUDGE, general increase in cholinergic neurotransmission, paralysis

Question 17

What is the use of pralidoxime, and what is the mechanism of this function?

Answer 17

USE: poisoning by nerve gas, insecticide

Works by regenerating the AChE that has been phosphorylated by an AChEI

Question 18

What is the use of soman (an AChEI)? How is exposure treated?

Answer 18

USE: volatile nerve gas

TX: pralidoxime and atropine before aging

Question 19

Which three cholinomimetics are used for glaucoma?

Answer 19

Pilocarpine, physostigmine, echothiophate

Question 20

Which two cholinomimetics are used for postoperative/neurogenic ileus and urinary retention?

Answer 20

Bethanechol, neostigmine

Question 21

Which three cholinomimetics are used in the treatment and evaluation of myasthenia gravis? Order them from shortest duration of action to longest.

Answer 21

edrophonium (5-15 mins), neostigmine (.5-2 hrs), pyridostigmine (3-6 hrs)