What does eserine mean?
Eserine is a naturally occurring alkaloid found in the seeds of Physostigma venenosum, the so-called Calabar bean, a plant native to West Africa. Chemically identical to physostigmine, it works by inhibiting the enzyme cholinesterase, thereby prolonging the action of the neurotransmitter acetylcholine. This property made it historically significant as one of the earliest effective treatments for glaucoma, where it lowers intraocular pressure when applied as eye drops, and it has also been studied and used in relation to conditions such as myasthenia gravis and certain cases of poisoning. The word carries a strongly scientific register and appears mainly in medical, pharmacological, and historical texts. Its origin is dramatic: it derives from the name of a poison once used in West African trials by ordeal, giving this now-benign clinical agent one of the most striking backstories in pharmacology.
nounA bitter crystalline alkaloid obtained from the seeds of the Calabar bean (Physostigma venenosum), used chiefly in medicine as a cholinesterase inhibitor, especially in the treatment of glaucoma and certain neurological disorders. Also known as physostigmine.
- The alkaloid physostigmine, extracted from the Calabar bean, used medically as a cholinesterase inhibitor, particularly in ophthalmology.
"The ophthalmologist prescribed drops containing eserine to reduce pressure within the patient's eyes."
"Pharmacists of the nineteenth century prized eserine as one of the first effective treatments for glaucoma."
"In the laboratory, eserine served as a standard inhibitor for studying acetylcholinesterase activity."
Rarely pluralized; the plural would refer only to multiple preparations, formulations, or samples containing the compound rather than to the substance itself, which behaves like an uncountable material noun.
"The pharmacy stocked several eserines, each prepared with a different stabilizing salt."
Eserine was first isolated from the notorious 'ordeal bean' of West Africa, a poison once administered by trial to determine guilt.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of eserine
Eserine entered English in the nineteenth century via German Eserin, coined by chemists who isolated the compound from the Calabar bean. The root is the native name éseré for the bean among peoples of coastal Cameroon, transmitted through European botanical and pharmacological literature. The alternative name physostigmine, derived from the genus name Physostigma, later became the preferred clinical term.
How eserine is actually used
Eserine is a technical term confined largely to pharmacology, medicine, and toxicology. In modern clinical practice it is more often referred to as physostigmine, its international nonproprietary name.
Easily confused with eserine
Ephedrine is a different alkaloid derived from Ephedra plants and used as a bronchodilator and stimulant, whereas eserine (physostigmine) comes from the Calabar bean and acts as a cholinesterase inhibitor.