Atropine is an alkaloid found in every part of the deadly nightshade (Atropa belladonna) and in certain other plants. Atropine (C12H23NO3N) is poisonous but is used in small amounts to treat inflammation of the iris (iritis) and corneal ulcer. It is also used in young children to dilate (widen) the pupil of the eye for the purpose of examination.
Atropine is commonly given as a premedication before general anesthesia to reduce secretions from the lungs and is also used as an emergency treatment for bradycardia (abnormally slow heartbeat).
Atropine is occasionally prescribed for its antispasmodic effects. It is sometimes combined with an antidiarrheal drug to relieve abdominal cramps accompanying diarrhea, and to treat motion sickness.