Neostigmine

Intramuscular
Neonatal myasthenia gravis

Intravenous
Reversal of neuromuscular blockade

Oral
Myasthenia gravis

Oral
Paralytic ileus and postoperative urinary retention

Parenteral
Paralytic ileus and postoperative urinary retention

Parenteral
Myasthenia gravis

Oral:
Continuous renal replacement therapy (CRRT): 50% of normal dose.

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

IM/IV:
Dose adjustment may be required.

Peritonitis, mechanical GI or urinary obstruction.

Patient w/ bronchial asthma, CV disorders (e.g. bradycardia, recent MI, hypotension), peptic ulcer disease, vagotonia, epilepsy, parkinsonism, hyperthyroidism. Patient who underwent recent intestinal or bladder surgery. Renal impairment. Childn. Pregnancy and lactation.

Nausea and vomiting, increased salivation, diarrhoea and abdominal cramps; hypersensitivity reactions (e.g. anaphylaxis, urticaria, angioedema); neuromuscular dysfunction in high doses of IV preparation.
Potentially Fatal: Resp failure, due to a combination of muscarinic, nicotinic and central effects or cardiac arrest.

IM/IV/Parenteral/PO/SC: C

Monitor ECG, BP and heart rate esp w/ IV use.

Symptoms: Muscarinic effects e.g. abdominal cramps, increased peristalsis, diarrhoea, nausea and vomiting, increased bronchial secretions, salivation, diaphoresis, miosis and nicotinic effects e.g. muscular cramps, fasciculations, general weakness. Bradycardia and hypotension may also occur. Management: Empty the stomach by gastric lavage. May give activated charcoal to decrease absorption. Artificial respiration should be instituted for severe resp depression. Give atropine sulfate 1-2 mg IV to control muscarinic effects.

May potentiate neuromuscular blockade w/ depolarising muscle relaxants (e.g. suxamethonium) resulting to prolonged apnoea. Drugs w/ neuromuscular blocking activity (e.g. aminoglycosides, clindamycin, colistin, cyclopropane, halogenated inhalational anaesth) may antagonise the effects of neostigmine. Reduced effects w/ quinine, chloroquine, hydroxychloroquine, quinidine, procainamide, propafenone, lithium. Prolonged bradycardia w/ β-blockers.

Description: Neostigmine inhibits the hydrolysis of acetylcholine by competing w/ acetylcholine for its binding site on acetylcholinesterase. It facilitates impulse transmission across neuromuscular junctions thus, enhancing cholinergic action. It also has a direct cholinomimetic effect on skeletal muscle and possibly on autonomic ganglion cells and neurons of the CNS.
Onset: 1-2 hr (oral); 20-30 min (IM).
Duration: 2-4 hr (oral); 2.5-4 hr (IM).
Pharmacokinetics:
Absorption: Poorly absorbed from the GI tract. Bioavailability: Approx 1-2%. Time to peak plasma concentration: 1-2 hr.
Distribution: Crosses the placenta and enters breast milk (small amounts). Volume of distribution: 0.12-1.4 L/kg (IV). Plasma protein binding: 15-25%.
Metabolism: Undergoes hepatic metabolism and hydrolysis by cholinesterases.
Excretion: Via urine, as unchanged drug and metabolites. Half-life: 42-60 min (oral); 51-90 min (IM); 24-113 min (IV).

Source: National Center for Biotechnology Information. PubChem Database. Neostigmine, CID=4456, https://pubchem.ncbi.nlm.nih.gov/compound/Neostigmine (accessed on Jan. 22, 2020)

Store between 20-25°C. Protect from light.

Neuromuscular Disorder Drugs

N07AA01 - neostigmine ; Belongs to the class of anticholinesterase. Used as parasympathomimetics.

Anon. Neostigmine. Lexicomp Online. Hudson, Ohio. Wolters Kluwer Clinical Drug Information, Inc. https://online.lexi.com. Accessed 30/07/2015.

Buckingham R (ed). Neostigmine. Martindale: The Complete Drug Reference [online]. London. Pharmaceutical Press. https://www.medicinescomplete.com. Accessed 30/07/2015.

Neostigmine Methylsulfate Injection, Solution (Fresenius Kabi USA, LLC). DailyMed. Source: U.S. National Library of Medicine. https://dailymed.nlm.nih.gov/dailymed/. Accessed 03/07/2015.