Atropine

Alkaloid, C1,H29 NO,, obtained from Atropa Belladonna, of which it is the active medicinal and poisonous principle. It is most commonly used in the form of the sulphate, to relieve pain and dilate the pupil in diseases of the eye, and to counteract the unpleasant and poisonous effects of opium, of which it is the physiological antidote.