LEHNE PHARM CHOLINERGIC AGONISTS &
CHOLINESTERASE INHIBITORS REVISION
QUESTION AND ANSWERS 100% A+ PASS EXAM
LATEST UPDATED 2026-2027.
1. Which receptor subtype is primarily responsible for the bradycardic effects
of acetylcholine in the heart?
A. M1
B. M2
C. M3
D. Nn
Correct answer: B
Rationale: M2 muscarinic receptors in the SA and AV nodes decrease heart
rate and conduction velocity.
2. Which drug is a direct-acting muscarinic agonist?
A. Neostigmine
B. Atropine
C. Bethanechol
D. Edrophonium
Correct answer: C
Rationale: Bethanechol directly stimulates muscarinic receptors, especially
in the bladder and GI tract.
3. Which effect is most likely after administration of a muscarinic agonist?
A. Bronchodilation
B. Increased heart rate
C. Increased salivation
D. Pupil dilation
Correct answer: C
Rationale: Muscarinic stimulation increases secretions including salivation.
,4. Which cholinergic receptor subtype mediates glandular secretion?
A. M1
B. M2
C. M3
D. Nn
Correct answer: C
Rationale: M3 receptors stimulate glandular secretion and smooth muscle
contraction.
5. Pilocarpine is mainly used to treat:
A. Hypertension
B. Glaucoma
C. Asthma
D. Arrhythmia
Correct answer: B
Rationale: Pilocarpine increases aqueous humor outflow via M3 receptors in
the eye.
6. Which enzyme is inhibited by cholinesterase inhibitors?
A. Monoamine oxidase
B. Acetylcholinesterase
C. Tyrosine hydroxylase
D. COMT
Correct answer: B
Rationale: These drugs block breakdown of acetylcholine at synapses.
7. Which drug is a reversible acetylcholinesterase inhibitor?
A. Organophosphates
B. Physostigmine
C. Parathion
D. Sarin
Correct answer: B
Rationale: Physostigmine reversibly inhibits acetylcholinesterase.
, 8. Neostigmine is commonly used in:
A. Asthma treatment
B. Myasthenia gravis
C. Parkinson’s disease
D. Epilepsy
Correct answer: B
Rationale: It increases acetylcholine at neuromuscular junctions improving
muscle strength.
9. Which cholinesterase inhibitor crosses the blood-brain barrier?
A. Neostigmine
B. Edrophonium
C. Physostigmine
D. Pyridostigmine
Correct answer: C
Rationale: Physostigmine is tertiary and crosses into the CNS.
10.Organophosphate toxicity is characterized by:
A. Dry skin
B. Mydriasis
C. SLUDGE symptoms
D. Hypertension only
Correct answer: C
Rationale: SLUDGE (salivation, lacrimation, urination, diarrhea, GI cramps,
emesis) reflects muscarinic excess.
11.Atropine works by:
A. Activating nicotinic receptors
B. Blocking muscarinic receptors
C. Inhibiting acetylcholine release
D. Increasing ACh synthesis
Correct answer: B
Rationale: Atropine is a competitive muscarinic antagonist.
CHOLINESTERASE INHIBITORS REVISION
QUESTION AND ANSWERS 100% A+ PASS EXAM
LATEST UPDATED 2026-2027.
1. Which receptor subtype is primarily responsible for the bradycardic effects
of acetylcholine in the heart?
A. M1
B. M2
C. M3
D. Nn
Correct answer: B
Rationale: M2 muscarinic receptors in the SA and AV nodes decrease heart
rate and conduction velocity.
2. Which drug is a direct-acting muscarinic agonist?
A. Neostigmine
B. Atropine
C. Bethanechol
D. Edrophonium
Correct answer: C
Rationale: Bethanechol directly stimulates muscarinic receptors, especially
in the bladder and GI tract.
3. Which effect is most likely after administration of a muscarinic agonist?
A. Bronchodilation
B. Increased heart rate
C. Increased salivation
D. Pupil dilation
Correct answer: C
Rationale: Muscarinic stimulation increases secretions including salivation.
,4. Which cholinergic receptor subtype mediates glandular secretion?
A. M1
B. M2
C. M3
D. Nn
Correct answer: C
Rationale: M3 receptors stimulate glandular secretion and smooth muscle
contraction.
5. Pilocarpine is mainly used to treat:
A. Hypertension
B. Glaucoma
C. Asthma
D. Arrhythmia
Correct answer: B
Rationale: Pilocarpine increases aqueous humor outflow via M3 receptors in
the eye.
6. Which enzyme is inhibited by cholinesterase inhibitors?
A. Monoamine oxidase
B. Acetylcholinesterase
C. Tyrosine hydroxylase
D. COMT
Correct answer: B
Rationale: These drugs block breakdown of acetylcholine at synapses.
7. Which drug is a reversible acetylcholinesterase inhibitor?
A. Organophosphates
B. Physostigmine
C. Parathion
D. Sarin
Correct answer: B
Rationale: Physostigmine reversibly inhibits acetylcholinesterase.
, 8. Neostigmine is commonly used in:
A. Asthma treatment
B. Myasthenia gravis
C. Parkinson’s disease
D. Epilepsy
Correct answer: B
Rationale: It increases acetylcholine at neuromuscular junctions improving
muscle strength.
9. Which cholinesterase inhibitor crosses the blood-brain barrier?
A. Neostigmine
B. Edrophonium
C. Physostigmine
D. Pyridostigmine
Correct answer: C
Rationale: Physostigmine is tertiary and crosses into the CNS.
10.Organophosphate toxicity is characterized by:
A. Dry skin
B. Mydriasis
C. SLUDGE symptoms
D. Hypertension only
Correct answer: C
Rationale: SLUDGE (salivation, lacrimation, urination, diarrhea, GI cramps,
emesis) reflects muscarinic excess.
11.Atropine works by:
A. Activating nicotinic receptors
B. Blocking muscarinic receptors
C. Inhibiting acetylcholine release
D. Increasing ACh synthesis
Correct answer: B
Rationale: Atropine is a competitive muscarinic antagonist.
