Derived from Atropa belladonna, a deadly nightshade, which compound is it?

• A. Epinephrine
• B. Scopolamine
• C. Atropine
• D. Morphine sulfate

Answer: (C)

Atropa belladonna houses tropane alkaloids that block muscarinic acetylcholine receptors, leading to anticholinergic effects. The compound most famously linked to deadly nightshade and used clinically as an antimuscarinic is atropine. It acts as a competitive antagonist at muscarinic receptors, which explains its typical effects: increased heart rate, reduced secretions, bronchodilation, dry mouth, and pupil dilation. Epinephrine and morphine sulfate aren’t derived from this plant—epinephrine is produced in the body and used as a catecholamine drug, while morphine comes from opium poppy. Scopolamine is another alkaloid from the same plant, but atropine is the classic, most commonly associated compound with Atropa belladonna in pharmacology contexts.