Cholinergic Pharmacology

Question 1

MoA of Direct acting cholinergic agonist (DACA)

Answer 1

Act directly on ACh receptos

Question 2

Adverse effects of DACA

Answer 2

Muscarinic Toxicity:
1) increased salivation and sweating
2) Blurred vision
3) Decreased HR and Bp
4) shortness of breath
5) Urinary frequency
6) CNS stimulation

Nicotinic Toxicity:
1) CNS stimulation
2) Fasciculation- parylsis
3) Very addictive

Question 3

what are the categories of DACA? give drug examples

Answer 3

Muscarinic
1) Pilocarpin (Glaucoma)
2) Bethanechol (Atonic bladder conditions)

Nicotinic
1) Nicotin
2) Varenciline (reduce nicotine craving)

Both
1) Acetylcholine
2) Carbachol

Question 4

Category of Benthanechol

Answer 4

DACA - Choline ester

Question 5

Indication of Benthanechol

Answer 5

-Atonic bladder conditions
- Postoperative/Postpartum urine retention

Question 6

MoA of Benthanechol

Answer 6

Activate bladder SM

Question 7

PK/PD Benthanechol

Answer 7

–> Resistant to AChE.
–> No nicotinic activity.
–> Used for urinary retention.

Question 8

Category of Pilocarpin

Answer 8

DACA- Alkaloids

Question 9

Indication Pilocarpin

Answer 9

Glaucoma/ Eye surgery

Question 10

MoA of Pilocarpine

Answer 10

Decrease Intraocular pressure (IOP)

Question 11

PK/PD of Pilocarpine

Answer 11

1) Contracts ciliary muscle of eye (open-angle glaucoma)
2) Pupillary sphincter (closed-angle
glaucoma)
3) Resistant to AChE.
4) Can cross blood-brain barrier
(BBB).
5) It is a potent stimulator of sweat,
tears, and saliva, open/closed angle glaucoma, xerostomia
(Sjögren syndrome).

Question 12

Category of Varenicline

Answer 12

Nictotic Agonist

Question 13

MoA of Varenicline

Answer 13

inhibit nicotinic receptors

Question 14

Indication of Varenciline

Answer 14

used to reduce nicotinic cravinings

Question 15

MoA of IAAC (Indirect Acting Anti-Cholinesterases)

Answer 15

Accumulation of Ach at the synaptic cleft —–> by inhibiting AchE

Question 16

What are the 2 types of IAAC?

Answer 16

1) Reversible —> short-acting (min-hr)
end in -ium or igmine
2) Irreversible –> long acting (days-weeks)
e.g. insect /pesticides (Orangophosphates), chemical weapons

Question 17

The effect of IAAC depend on?

Answer 17

1) Drug dose
2) Structure (tertiary or quaternary)
3) duration of action (Reversible/irreversible)

Question 18

Indications of IAAC

Answer 18

Antidote to:
1)Anti-cholenergics
2) Tricyclic anti-depressants
3) Narcotics

Question 19

List a few IAAC drugs

Answer 19

1) Physostigmine (glaucoma)
2) Neostigmine (Myasthenia gravis, urinary retention etc)
3) Donepezil (Mild/moderate Dementia & AD)
4) Edrophonium ( increase tone and parestalisis in GI)

Question 20

Adverse effects of IAAC

Answer 20

DUMBBELSS
1) Diarrhea
2) Urination
3) Miosis (pupil constiction)
4) Bradychardia
5) Bronchoconstriction
6) Excitation (of Skeletal Muscles and CNS)
7) Lacrimation
8) Salivation
9) Sweating

Question 21

MoA of Physostigmine

Answer 21

Antidote for anticholenergic toxicity

Question 22

Indication of Physostigmine

Answer 22

Glaucoma eye surgery –> decreaes intracoular pressure

Question 23

PK/PD of Physostigmine

Answer 23

Tertriay amine–> corsses the BBB –> enters the CNS

Question 24

Indication of Neostigmine

Answer 24

1) Myasthenia Gravis
2) Urinary retention
3) Postoperative/ neurogenic ileus
4) Reversal NM blockade

Question 25

MoA of Neostigmine

Answer 25

increase tone –> Atonic bladder condition

Question 26

Indication of Edrophonium

Answer 26

1) To increase tone & peristalisis in GI disorders
2) Cholenergic crisis:
-salivation
-lacrimation
-urination
-defecation

Question 27

MoA of Edrophonium

Answer 27

Increases ACh

Question 28

PK/PD of Edrophonium

Answer 28

Used to diagnose Myasthenia gravis –> replaced by an anti-AChRAB test

Question 29

Indication of Donepezil

Answer 29

Mild/Moderate Dementia and AD

Question 30

MoA of Donepezil

Answer 30

to increase cognetion

Question 31

PK/PD of Donepezil

Answer 31

• increases ACh
• Lipid soluble (CNS entery)
• 1st line for Alzehimer’s Disease