Brands, Medical Use, Clinical Data
Drug Category
- Neuromuscular Nondepolarizing Agents
Dosage Forms
- Solution (sterile, non-pyrogenic, with pH 3.5 to 5.0 containing mivacurium chloride equivalent to 2 mg/mL mivacurium in water for injection)
Brands / Synonyms
Mivacron; Mivacron
Indications
For inpatients and outpatients, as an adjunct to general anesthesia, to facilitate tracheal intubation and to provide skeletal muscle relaxation during surgery or mechanical ventilation.
Pharmacology
Mivacurium is a short-acting, nondepolarizing skeletal neuromuscular blocking agent which is hydrolyzed by plasma cholinesterase. Mivacurium results in a blockade of neuromuscular transmission by binding competitively with cholinergic receptors on the motor end-plate to antagonize the action of acetylcholine. The neuromuscular block produced by mivacurium is readily antagonized by anticholinesterase agents. The deeper the level of neuromuscular block at reversal, the longer the time required for recovery of neuromuscular function and the greater the dose of anticholinesterase agent required. Because spontaneous recovery after mivacurium is rapid, routine reversal may not always result in a clinical benefit.
Mechanism of Action
Mivacurium binds competitively to cholinergic receptors on the motor end-plate to antagonize the action of acetylcholine, resulting in a block of neuromuscular transmission. This action is antagonized by acetylcholinesterase inhibitors, such as neostigmine.
Absorption
Not Available
Toxicity
Overdosage with neuromuscular blocking agents may result in neuromuscular block beyond the time needed for surgery and anesthesia.
Biotrnasformation / Drug Metabolism
Extensive and rapid via enzymatic hydrolysis catalyzed by plasma cholinesterase. Biotransformation may be significantly slowed in patients with abnormal or decreased plasma cholinesterase activity, especially individuals with a homozygous atypical cholinesterase gene abnormality.
Contraindications
MIVACRON is contraindicated in patients known to have an allergic hypersensitivity to mivacurium chloride or other
benzylisoquinolinium agents, as manifested by reactions such as urticaria or severe respiratory distress or
hypotension. Use of MIVACRON from multiple-dose vials containing benzyl alcohol as a preservative is contraindicated
in patients with a known hypersensitivity to benzyl alcohol.
Multiple-dose vials of Mivacron contain benzyl alcohol, while single-dose vials do not. Use from multiple-dose
vials is contraindicated in patients with a known hypersensitivity to benzyl alcohol.
In newborn infants (children less than 1 month in age), benzyl alcohol has been associated with an increased
incidence of neurological and other complications which are sometimes fatal. I.V. preparations containing benzyl
alcohol should not be used in newborns.
Drug Interactions
Although MIVACRON (a mixture of three stereoisomers) has been administered safely following
succinylcholine-facilitated tracheal intubation, the interaction between MIVACRON and succinylcholine has not been
systematically studied. Prior administration of succinylcholine can potentiate the neuromuscular blocking effects of
nondepolarizing agents. Evidence of spontaneous recovery from succinylcholine should be observed before the
administration of MIVACRON.
The use of MIVACRON before succinylcholine to attenuate some of the side effects of succinylcholine has not been
studied.
There are no clinical data on the use of MIVACRON with other nondepolarizing neuromuscular blocking agents.
Isoflurane and enflurane (administered with nitrous oxide/oxygen to achieve 1.25 M.C. decrease the ED50
of MIVACRON by as much as 25% (see CLINICAL PHARMACOLOGY: Pharmacodynamics and Individualization of
Dosages). These agents may also prolong the clinically effective duration of action and decrease the average
infusion requirement of MIVACRON by as much as 35% to 40%. A greater potentiation of the neuromuscular blocking
effects of MIVACRON may be expected with higher concentrations of enflurane or isoflurane. Halothane has little or no
effect on the ED50 , but may prolong the duration of action and decrease the average infusion requirement
by as much as 20%.
Other drugs which may enhance the neuromuscular blocking action of nondepolarizing agents such as MIVACRON include
certain antibiotics (e.g., aminoglycosides, tetracyclines, bacitracin, polymyxins, lincomycin, clindamycin, colistin,
and sodium colistimethate), magnesium salts, lithium, local anesthetics, procainamide, and quinidine. The
neuromuscular blocking effect of MIVACRON may be enhanced by drugs that reduce plasma cholinesterase activity (e.g.,
chronically administered oral contraceptives, glucocorticoids, or certain monoamine oxidase inhibitors) or by drugs
that irreversibly inhibit plasma cholinesterase .
Resistance to the neuromuscular blocking action of nondepolarizing neuromuscular blocking agents has been
demonstrated in patients chronically administered phenytoin or carbamazepine. While the effects of chronic phenytoin
or carbamazepine therapy on the action of MIVACRON are unknown, slightly shorter durations of neuromuscular block may
be anticipated and infusion rate requirements may be higher.
Some drug interactions are:
- birth control pills
- corticosteroids
- medicines for angina or high blood pressure
- medicines for pain
- medicines to control seizures such as phenytoin or carbamazepine
- certain antibiotics given by injection
- cisplatin
- edrophonium
- neostigmine
- polymyxin B or bacitracin
- local anesthetics such as procaine
- general anesthetics
- succinylcholine or other muscle relaxants
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