Eserine
Generic: Physostigmine
Medicinal Chemistry
Molecular Weight
275.35
Molecular Formula
C15H21N3O2
IUPAC Name
(3aS,8aR)-1,3a,8-trimethyl-1,2,3,3a,8,8a-hexahydropyrrolo[2,3-b]indol-5-yl N-methylcarbamate
Pharmacognosy
Biological Source
Physostigma venenosum (Calabar bean)
Active Constituents
Physostigmine
Pharmacology & Synthesis
Mechanism of Action
Reversibly inhibits acetylcholinesterase, increasing acetylcholine at synapses.
Pharmacokinetics (ADME)
A: Well absorbed.
D: Highly lipophilic, crosses BBB.
M: Hydrolysis by cholinesterases.
E: Renal.
Pharmacodynamics
Enhances parasympathetic activity, central arousal (antidote for anticholinergic toxicity).
Synthesis Pathway
Biosynthesized from tryptophan.
Safety, Warnings & Interactions
Adverse Effects
Bradycardia, salivation, seizures, muscle fasciculations.
Contraindications
Asthma, gangrene, cardiovascular disease, mechanical GI obstruction.
Drug Interactions
Depolarizing neuromuscular blockers (prolongs action).
Pharmaceutics & Compendia
Dosage Forms
Injection, Ophthalmic ointment
Official Compendia
USP