Drugs Affecting Nicotinic Receptors MCQs PDF
1. In 1856, which scientist reported that the site of action of curare was the junction between nerve and muscle?
a. Bernard.
b. Langley.
c. Ambroise Paré.
d. Galen.
2. Which of the following is not true about nicotine?
a. Nicotine is the principal psychoactive ingredient in tobacco products.
b. It stimulates transmission at autonomic ganglia and at nicotinic synapses in CNS.
c. It is a selective depolarizing drug at nicotinic receptors.
d. Nicotine has stimulatory effect only on ganglionic transmission.
3. Nicotine activates various sensory fibers equipped with nicotinic receptors, EXCEPT
a. mechanoreceptors in the lung.
b. nociceptive nerve endings.
c. chemoreceptors in the carotid body.
d. mechanoreceptors in heart.
4. Usual amounts of nicotine absorbed during cigarette smoking cause all of the following, EXCEPT
a. mild cardiovascular stimulation.
b. CNS stimulation.
c. physical dependence.
d. decreased gastrointestinal activity.
5. Nicotine cessation triggers an acute withdrawal syndrome that causes all of the following, EXCEPT
a. cognitive impairment.
b. sleep disturbances.
c. convulsions.
d. irritability and anxiety.
6. Dimethylphenylpiperazinium is how many times more potent than nicotine?
a. Three times.
b. Four times.
c. Two times.
d. Same potency.
7. Ganglionic-blocking agents have the following actions, EXCEPT
a. marked xerostomia.
b. cause paralytic ileus and constipation.
c. sympathetic stimulation of the eccrine sweat glands is inhibited.
d. increase in blood pressure.
8. Which of the following statement about d-tubocurarine is true?
a. It incorporates one cationic nitrogen site into a rigid molecular structure.
b. It is a monoquaternary amine.
c. It is a noncompetitive, neuromuscular-blocking drug.
d. It causes spastic paralysis of muscles.
9. What is the approximate percentage of the ACh receptors that must normally be blocked to produce any clinically apparent effect on muscle function?
a. 60%.
b. 70%.
c. 80%.
d. 50%.
10. The major side effect seen with curare is
a. hypertension.
b. hypotension.
c. paralytic ileus.
d. bronchodilation.
11. Postjunctional stimulation by succinylcholine is responsible for an increased muscle tension observable with some muscles, especially
a. masseter.
b. orbicularis oris.
c. levator anguli oris.
d. mentalis.
12. Which of the following is not an intermediate-acting neuromuscular receptor-blocking agent?
a. Atracurium.
b. Cisatracurium.
c. Rocuronium.
d. Pancuronium.
13. Which of the following is not true about succinylcholine?
a. It is a short-acting depolarizing blocker of skeletal muscle lasting for about 5 to 10 minutes.
b. It tends to lower intraocular tension.
c. It is contraindicated in patients suspected to have brain tumors.
d. It is known to cause anaphylaxis with a reported incidence of one or two per 10,000 administrations.
14. Characteristics of an ideal neuromuscular blocker is,
a. it should not induce tachyphylaxis.
b. it should be irreversible.
c. it should have a slow onset of action.
d. it would liberate histamine from muscle or other tissues.
15. Which of the following neuromuscular blocker has the most prominent histamine release ability from mast cells?
a. Atracurium.
b. Cisatracurium.
c. Vecuronium.
d. Tubocurarine.
16. Mivacurium has a clinical duration of action of
a. 15–20 minutes after an intubating dose.
b. 5–10 minutes after an intubating dose.
c. 30–40 minutes after an intubating dose.
d. 2–4 minutes after an intubating dose.
17. General therapeutic uses of neuromuscular-blocking agents do not include which of the following?
a. Endotracheal intubation.
b. Neuromuscular-blocking agents are administered to reduce the severity of spasms in
patients of tetanus.
c. Electroconvulsive therapy.
d. Succinylcholine is used to produce a short-lived muscular contraction to permit numerous brief nonsurgical manipulations, such as bronchoscopy.
18. Which of the following neuromuscular-blocking drug has a rapid onset of action?
a. Atracurium.
b. Cisatracurium.
c. Rocuronium.
d. Vecuronium.
19. Which of the following does not inhibit plasma cholinesterase?
a. Edrophonium.
b. Neostigmine.
c. Pyridostigmine.
d. Echothiophate.
20. Which of the following drugs is not spasmolytic?
a. Diazepam.
b. Baclofen.
c. Tizanidine.
d. Acetylcholine.
21. Which of the following statements is true?
a. Patients experience less sedation with baclofen than with diazepam.
b. Patients experience more sedation with baclofen than with diazepam.
c. Patients experience similar sedation efficacy with baclofen and diazepam.
d. Baclofen does not have sedative property.
22. The site of action for dantrolene is
a. mitochondria.
b. nucleus.
c. golgi bodies.
d. sarcoplasmic reticulum.
23. Which of the following is not true about hemicholinium?
a. Hemicholinium acts by blocking neuronal uptake of choline.
b. Blockade of neuromuscular transmission by hemicholinium is rapid in onset but is accelerated by increased motor neuron activity.
c. Hemicholinium inhibits choline transport in all peripheral cholinergic nerves; it affects transmission at all cholinergic synapses and junctions.
d. Hemicholinium has no clinical applications at present.
24. Which of the following is not true about botulinum toxin?
a. The toxin is produced by Clostridium botulinum.
b. Botulinum toxin acts on the motor nerve terminal to prevent the release of ACh in response to the arrival of an axonal action potential.
c. The toxin interferes with the efflux of intracellular Ca11 into the nerve terminal.
d. Botulinum toxin affects all peripheral cholinergic nerves.
25. Tetrodotoxin is found in tissues of
a. bubblefish.
b. toadfish.
c. balloonfish.
d. pufferfish.
