Depolarizing neuromuscular blocking agents

Mechanism of Action A depolarizing neuromuscular blocking agent that causes the release of acetylcholine and inhibits cholinesterase. Therapeutic Effect Results in a spastic paralysis of the worm and consequent expulsion from the host s intestinal tract. 

Both pyrantel (13a) and morantel (13b) are depolarizing neuromuscular blocking agents that stimulate ganglia and also possess acetylcholine-like actions on smooth muscle. 

Pyrantel pamoate [pi RAN tel] along with mebendazole is effective in the treatment of infections caused by roundworms, pinworms (see Figure 36.4), and hookworms. Pyrantel pamoate is poorly absorbed orally and exerts its effects in the intestinal tract. It acts as a depolarizing neuromuscular blocking agent, causing persistent... 

A variety of other tropane alkaloids have been isolated of which the most important is anatoxin-A, a highly toxic nACh-R agonist and depolarizing neuromuscular blocking agent deriving from Anabaena cyanobacterium species that can contaminate inland waters. 

Hughes R, Chappie DJ. Effects on non-depolarizing neuromuscular blocking agents on peripheral autonomic mechanisms in cats. Br J Anaesth 1976 48(2) 59-68. 

Burns are associated with resistance to atracurium (43), as for several other non-depolarizing neuromuscular blocking agents. The EC50 is increased and dose requirements may be increased by up to 2-3 times. The resistance varies with the burn area and the time from injury (SEDA-12, 116), being maximal at 15 0 days in patients repeatedly anesthetized. 

In contrast to reports on other non-depolarizing neuromuscular blocking agents, resistance to atracurium has not been found in patients taking long-term carbamazepine (SEDA-13, 104) (58). 

From animal experiments (8) it seems hkely that drug interactions with atracurium will be similar to those for other non-depolarizing neuromuscular blocking agents. Laudanosine has been reported to increase the MAC for halothane in animals (61). 

Hughes R, Payne JP, Sngai N. Stndies on fazadinium bromide (AH 8165) a new non-depolarizing neuromuscular blocking agent. Can Anaesth Soc J 1976 23(l) 36-47. 

Wierda JM, Kleef UW, Lambalk LM, Kloppenburg WD, Agoston S. The pharmacodynamics and pharmacokinetics of Org 9426, a new non-depolarizing neuromuscular blocking agent, in patients anaesthetized with nitrous oxide, halothane and fentanyl. Can J Anaesth 1991 38(4 Pt l) 430-5. 

Patients with burns require more D-tubocurarine (and higher plasma concentrations) for the same degree of blockade compared with non-burned patients (6). The mechanism is not known, but it appears not to be altered pharmacokinetics (7). The resistance to non-depolarizing neuromuscular blocking agents (SEDA-8,136) appears to be influenced by the size of the body surface area burned and by the time which has elapsed since the injury (see Atracurium). In extensive burns dose requirements are increased approximately by a factor of 2-3. 

Acute administration of phenytoin (10 mg/kg intravenously) has been reported to enhance slightly, but statistically significantly, steady blockade maintained by an infusion of vecuronium (SEDA-15, 124) (46). This is in contrast to reports of resistance to non-depolarizing neuromuscular blocking agents, including vecuronium, associated with long-term phen)4 oin (SEDA-13,104) (47). 

Marshall RJ, McGrath JC, Miller RD, Docherty JR, Lamar JC. Comparison of the cardiovascular actions of ORG NC 45 with those produced by other non-depolarizing neuromuscular blocking agents in experimental animals. Br J Anaesth 1980 52(Suppl l) S21-32. 

SUtilains [ban, inn, usan] (BAX 1515 Travase ) is an ENZYME derived from Bacillus subtilis. It is a proteolytic enzyme used for wound debridement in moist conditions, suxamethonium chloride [ban. inn] (succinyichoiine chloride [usan] suxamethonium bromide [ban] succinoylcholine Scoline Quelicin Anectine ) is a bistrimethylethanaminium derivative, a NICOTINIC CHOLINOCEPTOR AGONIST, a (depolarizing) NEUROMUSCULAR BLOCKING AGENT, which can be used as a SKELETAL MUSCLE RELAXANT in anaesthesia relaxant. Its action is short-lived due to hydrolysis by plasma cholinesterase, suxamethonium bromide suxamethonium chloride. 

Clinically important, potentially hazardous interactions with aminoglycosides, non-depolarizing neuromuscular blocking agents... 

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