Parasympathetic Medications

Question 1

Parasympathetic Nervous System

Answer 1

-Cholinergic

-Primary neurotransmitter is acetylcholine

Question 2

Cholinergic Receptors

Answer 2

1. Nicotinic receptors
2. Muscarinic receptors

Question 3

What is the enzyme that breaks down acetylcholine?

Answer 3

Acetylcholinesterase (or cholinesterase) is the enzyme that breaks down acetylcholine

A cholinesterase inhibitor drug would BLOCK this enzyme and the body would in essence have MORE acetylcholine available

Question 4

Cholinergic MOA

Answer 4

Direct acting-bind directly to the cholinergic receptors and activate a response (Direct key and lock)

Indirect acting aka inhibitors- also known as cholinesterase inhibitors because they don’t allow the acetylcholine to be broken down

Question 5

MUST KNOW

Answer 5

Anticholinesterase(or cholinesterase inhibitor) increases cholinergic activity.- stops breakdown of acetylcholine.

Anticholinergic inhibits/reduces cholinergic activity.- suppresses acecylcholine.

Question 6

Uses of parasympathomimetics

Answer 6

1. Promote GI function (treat paralytic ileus)
2. Promote GU function (treat urinary retention)
3. Promote muscle activity (treat myasthenia gravis; reverse neuromuscular blocking agents aka paralytics)
4. Treat glaucoma

Question 7

Direct Cholinergics

Answer 7

-bethcanechol (help urinate)
-pilocarpine (dry mouth)

Question 8

Indirect Cholingerics (anticholinesterase)

Answer 8

“Stigmine” Family
1. neostigmine- drug of choice for Myas Gravis
2. pyridostigmine
3. physostigmine

Edrophonium (Tensilon) used to diagnose MG

Question 9

ADRs of Cholinergics
“SLUDGEM + brady and hypotension”

Answer 9

Salivation (drooling)
Lacrimation (tearing)
Urinary frequency and incontinence
Defecation/Diarrhea; Diaphoresis
Gastrointestinal cramps & abdominal pain
Emesis (vomiting)
Miosis (small pupils)

Question 10

What is the antidote for cholinergic overload?
“too much acetylcholine”

Answer 10

Atropine (anticholinergic)

Question 11

Anti-Cholinergic Medications

Answer 11

1. Treat COPD/asthma
   tiotropium , ipratropium
2. Pre-op med to decrease secretions or treat symptomatic bradycardia
   atropine
3. Treat hypermotility or hypersecretion of GI tract (such as diarrhea, ulcers)
   glycopyrrolate
4. Precent N/V- scopolamine (“Scop patch”) {major use is anti-motion sickness drug for people going on cruise}
5. Decrease involuntary muscle activity associated with some neurological diseases
   benztropine– for Parkinson’s disease
6. Dilate and paralyze pupil for eye exams or eye surgery
   tropicamide