Physostigmine
Mechanism :
It is an anticholinesterase agent used as a muscle-relaxant. It is used in the diagnosis and treatment of myasthenia gravis. It is used in combination with other drugs to relieve intra-ocular pressure encountered in glaucoma. It is the antidote used for atropine poisoning.
Indication :
- For the treatment of glaucoma
- Treatment of severe anticholinergic toxicity.
Contraindications :
Hypersensitive to sulfites, GI obstruction, GU tract obstruction, Asthma, Gangrene, Diabetes mellitus, Severe cardiovascular disease, Arrhythmias, Glaucoma, angle-closure, Neonates.
Dosing :
Anticholinergic drug overdosage:
Initially 0.02 mg/kg/dose IV over 1 min. Maybe repeated at 5-10 min interval if required. Maximum dose: 0.5 mg/min and cumulative dose: 2 mg.
Adverse Effect :
Cholinergic crisis, seizures, tremor, fasciculation, bronchoconstriction, bradycardia, diaphoresis, hallucinations, hypotension and vomiting.
Interaction :
Avoid/Use Alternative:
Bethanechol, Cevimeline, Pilocarpine, Succinylcholine.
Hepatic Dose :
No dose adjustment recommended.