Description and indication for use

Neostigmine is an antagonist to cholinesterase, the enzyme which destroys acetylcholine.  This inhibition leads to accumulation of naturally occurring acetylcholine, producing generalized cholinergic responses (miosis, increased skeletal and intestinal muscle tone, constriction of bronchi and ureters, bradycardia, stimulation of salivary and sweat gland secretions).

Neostigmine is used to test for and treat Myasthenia Gravis, and for the reversal of neuromuscular blocking agents.

Dose

To test for Myasthenia Gravis

IV and IM:

0.05 mg/kg once only.

Antagonise cholinergic effects with Atropine 20 micrograms/kg.

To treat Myasthenia Gravis   

IV, IM and SC:

0.01 to 0.04 mg/kg/dose every 2 to 4 hours, half an hour before feeding.       

Reversal of non-depolarising neuromuscular blocking agents

0.05 to 0.15 mg/kg with Atropine 20 micrograms/kg.

Reconstitution/Dilution

Ampoule =  0.5mg in 1mL

IV and IM:

No dilution required.

Route and method of administration

IV and IM:

Give only when medical staff in attendance

Administer IV over 1 minute.

Side effects

Miosis.

Nausea, vomiting, abdominal cramps, increased gastric secretions, diarrhoea.

Increased bronchial secretions, bronchospasm.  Respiratory depression/arrest are usually the result of an overdose.

Bradycardia. Tachycardia/cardiac arrest are usually the result of an overdose.

Muscle weakness.

Skin rash.

Excessive salivation and sweating.

Special precautions

Use cautiously in patients with bronchospasm or cardiac arrhythmias.

Contraindications:

Intestinal and urinary obstruction.

Hypersensitivity.

Hypotension.

Bradycardia.

Incompatibilities

Neostigmine has few known incompatibilities but should not be mixed directly with other drugs.

Drug interactions

Nursing responsibilities

Maintain patient on cardio/respiratory monitor.

Assist in maintaining a patent airway and adequate ventilation.