Neuromuscular Blockers

Pipecuronium Bromide

Pipecuronium bromide is an aminosteroidal competitive neuromuscular blocker (see Atracurium). Pipecuronium is reported to have no significant cardiovascular adverse effects or histamine-related effects. On intravenous injection muscle relaxation occurs within 2.5 to 3 minutes with a duration of action of about 30 minutes to 2 hours, depending on the dose.

Neuromuscular Blockers

Neuromuscular blockers (myoneuronal blockers) affect transmission at the neuromuscular junction and are used as adjuncts to general anaesthesia, particularly to enable adequate muscle relaxation to be achieved with light anaesthesia. There are 2 main types of neuromuscular blockers: competitive (non-depolarising neuromuscular blockers) and depolarising neuromuscular blockers (Table: Classification of neuromuscular blockers). Competitive neuromuscular blockers act by competing with acetylcholine for receptors on the motor end-plate.

Pancuronium Bromide

White, yellowish-white, or slightly pink, hygroscopic crystalline powder. Very soluble to freely soluble in water; freely soluble in alcohol; very soluble in dichloromethane.

Tubocurarine Chloride

A white or slightly yellowish crystalline powder. Soluble in water and in alcohol; practically insoluble in acetone; dissolves in solutions of alkali hydroxides. A 1% solution in water has apH of 4.0 to 6.0.

Alcuronium Chloride

A white or slightly greyish-white, crystalline powder. Freely soluble in water and in methyl alcohol; soluble in alcohol; practically insoluble in cyclohexane. Store under nitrogen in an airtight container.

Atracurium Besilate

A white to yellowish-white, slightly hygroscopic powder. It contains 55.0 to 60.0% of the cis-cis isomer, 34.5 to 38.5% of the cis-trans isomer, and 5.0 to 6.5% of the trans-trans isomer.

Gallamine Triethiodide

A white, or almost white, hygroscopic powder. Very soluble in water; slightly soluble in alcohol; practically insoluble in dichloromethane.

Mivacurium Chloride

See under Atracurium for details regarding the incompatibility of neuromuscular blockers. As for competitive neuromuscular blockers in general (see Atracurium).