neostigmine methylsulfate: clinical use

Prescribing considerations

• Confirm the indication and appropriate administration route.
• For reversal, establish spontaneous recovery from non-depolarising blockade before administration.
• Ensure atropine is immediately available; account for baseline bradycardia before intravenous use.
• Use extreme caution in asthma and assess cardiovascular risk in bradycardia, arrhythmia or recent coronary occlusion.
• Use cautiously with epilepsy, vagotonia, hyperthyroidism, peptic ulceration, parkinsonism or an intestinal anastomosis.

Contraindications and cautions

• Hypersensitivity to neostigmine methylsulfate or an excipient.
• Mechanical gastrointestinal or urinary obstruction.
• Peritonitis or doubtful bowel viability.
• Concomitant use with depolarising muscle relaxants such as suxamethonium.

Monitoring

• Heart rate, rhythm and blood pressure.
• Respiratory function, bronchospasm and airway secretions.
• Neuromuscular recovery or control of myasthenic weakness.
• Features of excessive cholinergic activity, including gastrointestinal symptoms, sweating, salivation, twitching and worsening weakness.

Clinical pharmacology

Neostigmine is a reversible acetylcholinesterase inhibitor and quaternary ammonium compound with limited gastrointestinal and central nervous system penetration. After parenteral administration it is partly hydrolysed and excreted in urine as unchanged medicine and metabolites.

Formulation and product differences

• The selected product is a single-agent sterile injection rather than a fixed combination with an antimuscarinic.
• It may be administered intravenously, intramuscularly or subcutaneously according to indication.
• It is supplied in single-use glass ampoules; discard any remainder after opening.
• Protect from light and store below 25°C. Stability after dilution cannot be guaranteed.

Injection

Route: Parenteral

Strengths: 2.5 mg/1 mL