Cholinergic Drug Lec. 3

Question 1

What is drug act NONDEPOLARIZING NM blockers;

Answer 1

Tubocurarine

Question 2

What is drug act DEPOLARIZING NM blockers

Answer 2

Succinylcholine

Question 3

What is drug act NONDEPOLARIZING NM blockers with Short –acting

Answer 3

Mivacurium 20 min,gallamine

Question 4

What is drug act NONDEPOLARIZING NM blockers Intermediate-acting

Answer 4

Atracurium, Cisatracurium , Rocuronium and vencuronium
30 min

Question 5

What is drug act NONDEPOLARIZING NM blockers; Long-acting:

Answer 5

Pancuronium 40 min

Question 6

Who we can stoped the effect of NONDEPOLARIZING NM blockers

Answer 6

Their action can be overcome by increasing conc. of acetylcholine in the synaptic gap(by ihibition of acetyle choline estrase enzyme)
• e.g.: Neostigmine ,physostigmine edrophonium

Question 7

What the drug is administered before neostigmine, to prevent the parasympathetic effects of acetylcholine by blocking muscarinic receptors

Answer 7

Atropine

Question 8

What are drugs from Non-depolarizing Agents (Competitive Blockers) that metabolised in liver and we cannot give it in patient with liver problem

Answer 8

vecuronium, rocuronium)

Question 9

What are drugs from Non-depolarizing Agents (Competitive Blockers) that cannot give it in patient with renal problem?

Answer 9

(tubocurarine, mivacurium, metocurine)

Question 10

What is drug is degraded spontaneously in plasma by ester hydrolysis (Hofmann elimination),it releases histamine and can produce a fall in blood pressure ,flushing and bronchoconstriction. is metabolized to laudanosine ( which can provoke seizures?

Answer 10

Atracurium

Question 11

What is drug degraded spontaneously in plasma and by ester hydrolysis and does not accumulate and hence it is used in patients with hepatic
and renal failure

Answer 11

Cisatracurium

Question 12

What is
Unwanted effects of NONDEPOLARIZING NM blockers;

Answer 12

Fall in arterial pressure chiefly a result to ganglion block , may also be due to histamine release this may give rise to bronchospasm (especially with tubocurarine ,mivacurium ,and atracurium)
• Gallamine and pancuronium block, muscarinic receptors also, particularly in heart which may results in to tachycardia.

Question 13

What are ACTIONS of NONDEPOLARIZING NM blockers

Answer 13

• All the muscles are not equally sensitive to blockade.
• Small and rapidly contracting muscles are paralyzed first.
• Respiratory muscles are last to be affected and first to recover.

Question 14

What is drug with in DEPOLARIZING AGENTS

Answer 14

Suxamethonium ( succinylecholine)
(scoline)

Question 15

Whate the phases of DEPOLARIZING AGENTS drugs

Answer 15

1. Phase I block (= depolarizing)
2. Phase II block (Desensitizing)

Question 16

What are Pharmacokinetics of DEPOLARIZING AGENTS

Answer 16

• When rapid endotracheal intubations is required.
• Electroconvulsive shock therapy.

Question 17

Unwanted effects of DEPOLARIZING AGENTS

Answer 17

Bradycardia preventable by atropine.
• Hyperkalemia in patients with trauma , burns, R-F
• this may cause dysrhythmia or even cardiac arrest.
• Increase intraocular pressure due to contracture of extra ocular muscles .
• increase intragastric pressure which may lead to emesis and aspiration of gastric content.
• Increase intracranial pressure
• Malignant hyperthermia: rare inherited condition probably caused by a mutation of Ca++ release channel of sarcoplasmic reticulum, which results muscle spasm and dramatic rise in body temperature. (This is treated by cooling the body and administration of Dantrolene)
• Prolonged paralysis: due to factors which reduce the activity of plasma cholinesterase
• genetic variants as abnormal cholinesterase, its severe deficiency.
• anti -cholinesterase drugs
• neonates, old age
• liver disease

Question 18

What are Contraindications of succinylcholine

Answer 18

History of malignant hyperthermia
• Acute narrow angle glaucoma
• Penetrating eye injury
• Allergy to succinylcholine
• Extensive muscle trauma & burn
• Cerebrovascular accident
• Peptic ulcer
• C/I in case of head injury

Question 19

What are drugs act muscarinic receptors also, particularly in heart which may results in to tachycardia?

Answer 19

Gallamine and pancuronium