Neostigmine
Mechanism :
Neostigmine inhibits the hydrolysis of acetylcholine by competing with acetylcholine for attachment to acetylcholinesterase at sites of cholinergic transmission. It enhances cholinergic action by facilitating the transmission of impulses across neuromuscular junctions. It also has a direct cholinomimetic effect on skeletal muscle and possibly on autonomic ganglion cells and neurons of the central nervous system.
Indication :
- Myasthenia gravis
- Muscle relaxant - reversal of non-depolarising muscle relaxant
Contraindications :
Contraindicated in patients with known hypersensitivity to the drug. Because of the presence of the bromide ion, it should not be used in patients with a previous history of reaction to bromides. It is contraindicated in patients with peritonitis or mechanical obstruction of the intestinal or urinary tract.
Dosing :
Myasthenia gravis:
Diagnosis:
Treatment:
0.01-0.04 mg/kg IV/IM/SC every 2-3 hours and as and when needed.
Reversal of non-depolarising neuromuscular blockade:
0.03-0.07 mg/kg I. Max: 0.07 mg/kg IV or a total of 5 mg, whichever is lesser.
Adverse Effect :
Cardiac arrhythmias, cardiac arrest, syncope, hypotension, increased oral, pharyngeal and bronchial secretions, and dyspnea. Following injectables: respiratory depression, respiratory arrest and bronchospasm may occur.
Other: allergic reactions (rash, urticaria) and anaphylaxis, dizziness, loss of consciousness, drowsiness, convulsions, headache, dysarthria, miosis, visual changes, nausea, emesis, flatulence and increased peristalsis, increased salivation, muscle cramps, spasms, arthralgia.
Interaction :
Aminoglycosides, Chlorpromazine, Clindamycin, Colistin, Imipenem/Cilastatin, Lithium, Procainamide and Quinidine: Effects of neostigmine are antagonized.
Acetazolamide, Ampicillin, Aspirin, Chloroquine, Dipyridamole, Erythromycin, Hydroxychloroquine, Ketoprofen and Penicillamine: May worsen myasthenia and thus diminish the effect of neostigmine.
Beta-Blockers: Can worsen bradycardia.
Atracurium, Tubocurarine, Pancuronium and Vecuronium: Antagonised.
Renal Dose :
Dose in Renal Impairment GFR (mL/min)
20-50 | 50–100% of normal dose |
10-20 | 50–100% of normal dose |
<10 | 50–100% of normal dose |
Dose in Patients undergoing Renal Replacement Therapies
CAPD | Unknown dialysability. Dose as in GFR<10 mL/min |
HD | Unknown dialysability. Dose as in GFR<10 mL/min |
HDF/High flux | Unknown dialysability. Dose as in GFR<10 mL/min |
CAV/VVHD | Unknown dialysability. Dose as in GFR=10–20 mL/min |
Hepatic Dose :
No dose adjustments are recommended.