Neostigmine information from DrugsUpdate  

Pharmacodynamics

Pharmacokinetics

Neostigmine reversibly inhibits acetylcholinesterase and thus potentiates the nicotinic and muscarinic effects of acetylcholine. This facilitates the transmission of impulses across myoneural junction.

Onset
IM: 20-30 minutes. IV: 1-20 minutes.

Duration
IM: 2.5-4 hours. IV: 1-2 hours.

Absorption
Poorly absorbed from the GI tract (oral).

Distribution
CNS (poor penetration), crosses the placenta and enters breast milk (small amounts). Protein-binding: 15-25%.

Metabolism
Hepatic; hydrolysis by cholinesterases.

Excretion
Parenteral: Rapidly eliminated via urine (as unchanged drug and metabolites).

Neostigmine Indications / Neostigmine Uses

Information Not Available

Neostigmine Adverse Reactions / Neostigmine Side Effects

Increased salivation and sweating, nausea and vomiting, abdominal cramps, diarrhoea, allergic reactions, rash (bromide salt), miosis, increased bronchial secretions, bradycardia, bronchospasm, weakness, muscle cramps, fasciculation, hypotension.

Potentially Fatal: Anaphylaxis.

Precautions

Monitor
Frequently assess muscle strength and function in patient with myasthenia gravis or patient recovering from nondepolarizing neuromuscular blocking agent.

Overdosage
Symptoms: Muscle weakness, blurred vision, excessive sweating, tearing and salivation, nausea, vomiting, diarrhoea, hypertension, bradycardia, muscle weakness, paralysis. Management: Atropine sulfate inj should be readily available.

Special Precautions

Patients with epilepsy, bronchial asthma, bradycardia, recent MI, hypotension, vagotonia, hyperthyroidism, recent intestinal or bladder surgery, renal impairment, arrhythmias, peptic ulcer. Distinguish cholinergic crisis due to overdosage from myasthenic crisis. Pregnancy and lactation. Atropine should always be available when given by injection.

Other Drug Interactions

May reduce effects of anticholinergics. May increase effects of cholinergic agonists. Increased risk of bradycardia with digoxin, diltiazem, verapamil or β-blockers without intrinsic sympathomimetic activity. Increased muscle weakness and decreased response to anticholinesterases with corticosteroids. May increase effects of depolarising neuromuscular blockers. Effects may be antagonised by drugs with neuromuscular blocking activity e.g. aminoglycosides, clindamycin, colistin, cyclopropane, halogenated inhalational anaesthetics. Effects may be reduced by quinine, chloroquine, hydroxychloroquine, quinidine, procainamide, propafenone, lithium, β-blockers. Possible additive toxicity with ophthalmic use of anticholinesterases e.g. ecothiopate.

Other Interactions

Information Not Available

Dosage

Oral
Myasthenia gravis
Adult: As bromide: 15 mg every 3-4 hours. Total daily dose is 75-300 mg in divided doses. Individualise dosing intervals to maximal response.
Child: As bromide: 2 mg/kg daily, divided into doses and given every 3-4 hours. Total daily dose is 15-90 mg.

CrCl (ml/min)    Dosage Recommendation
10-50        50% of normal dose.
<10        25% of normal dose.

Oral
Paralytic ileus and postoperative urinary retention
Adult: As bromide: 15-30 mg.

CrCl (ml/min)    Dosage Recommendation
10-50        50% of normal dose.
<10        25% of normal dose.

Oral
Neonatal myasthenia gravis
Child: As bromide: 1-5 mg every 4 hours.

CrCl (ml/min)    Dosage Recommendation
10-50    50% of normal dose.
<10    25% of normal dose.

Intravenous
Reversal of neuromuscular blockade
Adult: As metilsulfate: 50-70 mcg/kg by IV injection over 60 seconds. Alternatively, 0.5-2 mg up to a max of 5 mg.
Child: As metilsulfate: Children: 0.025-0.08 mg/kg/dose. Infants: 0.025-0.1 mg/kg/dose.

CrCl (ml/min)    Dosage Recommendation
10-50        50% of normal dose.
<10        25% of normal dose.

Intramuscular
Diagnosis of myasthenia gravis
Adult: As metilsulfate: 0.02 mg/kg as a single dose. Discontinue all anticholinesterase medications for at least 8 hours prior to admin.
Child: As metilsulfate: 0.04 mg/kg as a single dose. Discontinue all anticholinesterase medications for at least 8 hours prior to admin.

Parenteral
Myasthenia gravis
Adult: As metilsulfate: 0.5-2.5 mg IM/SC at intervals, up to a total daily dose of 5-20 mg.
Child: As metilsulfate: 200-500 mcg IM/SC as single daily dose.

CrCl (ml/min)    Dosage Recommendation
10-50        50% of normal dose.
<10        25% of normal dose.

Parenteral
Paralytic ileus and postoperative urinary retention
Adult: As metilsulfate: 0.5 mg IM/SC.

CrCl (ml/min)    Dosage Recommendation
10-50    50% of normal dose.
<10    25% of normal dose.

Parenteral
Neonatal myasthenia gravis
Child: As metilsulfate: 50-250 mcg IM/SC every 4 hr.

CrCl (ml/min)    Dosage Recommendation
10-50        50% of normal dose.
<10        25% of normal dose.

Ophthalmic
Glaucoma
Adult: Instil 1-2 drops of 0.5% solution into the eyes 1-4 times daily.

Food(before/after)

Information Not Available

Neostigmine and Pregnancy

Caution when used during pregnancy

Category C: Either studies in animals have revealed adverse effects on the foetus (teratogenic or embryocidal or other) and there are no controlled studies in women or studies in women and animals are not available. Drugs should be given only if the potential benefit justifies the potential risk to the foetus.

Neostigmine and Lactation

Caution when used during lactation

Neostigmine and Children

Safety and efficacy not established

Neostigmine and Geriatic

Information Not Available

Neostigmine and Other Contraindications

Mechanical GI or urinary tract obstruction, peritonitis

Storage

Intramuscular
Store at 15-30°C. Protect from light. Do not freeze.

Intravenous
Store at 15-30°C. Protect from light. Do not freeze.

Oral
Store at 15-30°C.

Parenteral
Store at 15-30°C. Protect from light. Do not freeze.

Lab interference

Intramuscular
Store at 15-30°C. Protect from light. Do not freeze.

Intravenous
Store at 15-30°C. Protect from light. Do not freeze.

Oral
Store at 15-30°C.

Parenteral
Store at 15-30°C. Protect from light. Do not freeze.