Definition of physostigmine in English:

physostigmine

Pronunciation /ˌfīsōˈstiɡmēn/ /ˌfaɪsoʊˈstɪɡmin/

noun

Chemistry
  • A compound that is the active ingredient of the Calabar bean and is used medicinally in eye drops because of its anticholinergic activity.

    A tricyclic alkaloid; chemical formula: C₁₅H₂₁N₃O₂

    ‘Julian was interested in medicinal plants, particularly the Calabar bean whose active principle, physostigmine, was first isolated by the German chemists Jobst and Hesse in 1864.’
    • ‘The symptoms of anticholinergic overdose may be treated with physostigmine in a dosage of 1 to 2 mg given intramuscularly or intravenously at 20-minute intervals.’
    • ‘But since physostigmine could be isolated only from the Calabar bean, the drug was not readily available.’
    • ‘Compared with placebo, an infusion of physostigmine produced a 21% decrease in apnea-hypopnea index and a 23% increase in the minimum level of oxygen saturation.’
    • ‘Some authorities have recommended against the use of physostigmine because of its frequent association with increased bronchial secretions and its rare association with asystole.’

Origin

Mid 19th century from the modern Latin genus name Physostigma(to which the Calabar bean belongs) + -ine.