Parasympathetic Drugs (Cholinomimetic)

Question 1

Direct Acting Cholinomimetics

Answer 1

A. Choline Esters (ABC,M)
* Acetylcholine (N,M)
* Bethanecol (M)
* Carbachol (N,M)
* Methacholine (N,M)

B. Cholinergic Alkaloids
* Pilocarpine (M) Pilocarpus jaborandi
* Muscarine (M)
* Nicotine (N) Nicotiana tabacum
* Lobeline (N) Lobelia inflata
* Arecoline (N,M) Areca catechu; betel nut,
nga nga!
* Varenicline (N) - smoking cessation
* Cevimeline (M3) - smoking cessation

Question 2

Indirect-Acting Cholinomimetics

Answer 2

A. Short-Acting (Edrophonium)
* duration of action: 15-30 mins (average of 20 mins)
* chemical structure: Amino alcohol
* Edrophonium (Tensilon)
* Reversible inhibitor

B. Intermediate Acting (-tigmines)
* duration of action: 2-8 hours
* chemical structure: Carbamates / Carbamyl Esters
* Stigmine:
* Physostigmine
* Neostigmine
* Pyridostigmine
* Demecarium
* Amberonium
* reversible inhibitor

C. Long-acting
* chemical structure: Organophosphates
* Echothiopate (Medically useful)
* Isofluorophate
* Malathion
* Parathion
* Nerve gases (Sarin, Tabun, Soman)
* duration of exposure: <24-48 hours = potentially reversible
inhibition
* > or = 24-48 hours = irreversible

D. Drugs for Alzheimer’s Disease
* Rivastigmine
* Galantamine
* Donepezil
* Tacrine

Question 3

No clinical use, primary transmitter at cholinergic nerve endings

Answer 3

Acetylcholine

Question 4

Stimulate bladder or GI muscle without affecting heart rate or blood pressure; Enhance bladder tone; for post-op urinary retention

Answer 4

Bethanechol (Urecholine)

Question 5

Used in ophthalmic surgery (Cataract Surgery & Iridectomy)

Answer 5

Carbachol (Miostat, Carbastat)

Question 6

Diagnosis of Asthma

Answer 6

Methacholine

Question 7

Alkaloid found in Mushroom; Poison

Answer 7

Muscarine

Question 8

Chewing gums, transdermal patch used as Smoking deterrent

Answer 8

Nicotine

Question 9

Second line drug for glaucoma; Treatment of Sjogren Syndrome

Answer 9

Pilocarpine - Tertiary amine

Question 10

Synthetic muscarinic receptor agonist; treatment of sjogren syndrome

Answer 10

Cevimeline (Evoxac) - Selective activate of M3

Question 11

Smoking deterrent

Answer 11

Varenicline - Partial agonist at N alpha 4, B2

Question 12

Black Box warning of Varenicline

Answer 12

High risk of neuropsychiatric effects
- Mood Changes
- Erratic behavior
- Suicide ideation

Question 13

Diagnosis of myasthenia gravis

Answer 13

Edrophonium

Question 14

Treatment of myasthenia gravis

Answer 14

Carbamates (-stigmines)

Question 15

Antidote of Atropine Poisoning; Anti-glaucoma

Answer 15

Physostigmine - natural, tertiary amine

Question 16

Antidote for Tubocurarine Poisoning; Tx Myasthenia gravis & Post op ileus

Answer 16

Neostigmine, Pyridostigmine - Synthetic, polar

Question 17

Treatment of Chronic glaucoma that does not responds to more conservative therapy

Answer 17

Echothiopate, Isoflurophate

Question 18

Pesticide, treat head lice

Answer 18

Malathion

Question 19

Nerve gases, chemical warfare agents

Answer 19

Soman, Sarin

Question 20

Management of all stages of Alzheimers

Answer 20

Donepezil

Question 21

Management of Mild to Moderate Alzheimers

Answer 21

Galantamine, Rivastigmine

Question 22

Parasympathetic Toxicity

Answer 22

Diarrhea
Urination
Miosis
Bradycardia
Bronchoconstriction
Emesis
Lacrimation
Salivation
Sweating

Question 22

Parasympathetic Toxicity

Answer 22

Diarrhea
Urination
Miosis
Bradycardia
Bronchoconstriction
Emesis
Lacrimation
Salivation
Sweating