atropine

American  

[a-truh-peen, -pin] / ˈæ trəˌpin, -pɪn /

noun

Pharmacology.

1. a poisonous crystalline alkaloid, C 17 H 23 NO 3 , obtained from belladonna and other plants of the nightshade family, that prevents the response of various body structures to certain types of nerve stimulation: used chiefly to relieve spasms, to lessen secretions, and, topically, to dilate the pupil of the eye.

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atropine British  

/ ˈætrəˌpiːn, ˈætrəpɪn, -pɪn /

noun

1. a poisonous alkaloid obtained from deadly nightshade, having an inhibitory action on the autonomic nervous system. It is used medicinally in pre-anaesthetic medication, to speed a slow heart rate, and as an emergency first-aid counter to exposure to chemical warfare nerve agents. Formula: C 17 H 23 NO 3

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atropine Scientific  

/ ăt′rə-pēn′,-pĭn /

1. A poisonous, bitter, crystalline alkaloid derived from deadly nightshade and related plants. It is used as a drug to dilate the pupils of the eye and to inhibit muscle spasms. Chemical formula: C ₁₇ H ₂₃ NO ₃ .

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Etymology

Origin of atropine

1830–40; < New Latin Atrop ( a ) belladonna genus (< Greek átropos; see Atropos) + -ine ²

Example Sentences

The U.S. is a global outlier, as there are approved versions of low-dose atropine in all other major markets.

From The Wall Street Journal • Dec. 28, 2025

Walline, along with collaborators, are working on setting up clinical trials to either prevent or delay the onset of myopia in children, using low-dose atropine eye drops.

From National Geographic • Nov. 1, 2023

Current interventions to slow the progression include specialty pediatric contact lenses and FDA-approved eye drops containing atropine.

From Slate • Sep. 30, 2023

Despite its deadly potential, the nerve-gas antidote atropine sulphate can be extracted from it.

From BBC • Jul. 10, 2023

They are all, like atropine, mydriatic alkaloids, so-called from the effect on the eye.

From The Social Gangster by Reeve, Arthur B. (Arthur Benjamin)