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acetylcysteine

American  
[uh-seet-l-sis-tee-een, -in, uh-set-, as-i-tl-] / əˌsit lˈsɪs tiˌin, -ɪn, əˌsɛt-, ˌæs ɪ tl- /

noun

Pharmacology.

  1. a substance, C 5 H 9 NO 3 S, used in solution as an inhalant to dissolve mucus in the treatment of chronic bronchitis, asthma, and emphysema and also used as an antidote in acetaminophen poisoning.

Etymology

Origin of acetylcysteine

acetyl + cysteine

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

For decades, doctors have relied on a drug called acetylcysteine as an effective antidote for acetaminophen overdose.

From Science Daily • Jan. 18, 2026

The ongoing phase II trial is designed to determine whether adding fomepizole to standard acetylcysteine treatment can reduce liver damage in patients at high risk after acetaminophen overdose.

From Science Daily • Jan. 18, 2026

Participants are randomly assigned to receive either both medications or acetylcysteine alone.

From Science Daily • Jan. 18, 2026

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.