tri·​meth·​o·​prim | \ trī-ˈme-thə-ˌprim How to pronounce trimethoprim (audio) \

Definition of trimethoprim

: a synthetic antibacterial and antimalarial drug C14H18N4O3 used alone or in combination with sulfamethoxazole

Examples of trimethoprim in a Sentence

Recent Examples on the Web The usual treatment is trimethoprim/sulfamethoxazole, an antibiotic combination. Sarah Jacoby, SELF, "Here Are the Symptoms of Cyclosporiasis, the Illness Linked to Recalled Vegetable Trays," 9 July 2018 And, of those patients, nearly 35 percent filled a prescription for nitrofurantoin and nearly 8 percent filled a prescription for trimethoprim-sulfamethoxazole, per the CDC data. Korin Miller, SELF, "Here’s What You Need to Know About Treating a UTI While Pregnant," 18 Jan. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'trimethoprim.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of trimethoprim

1964, in the meaning defined above

History and Etymology for trimethoprim

tri- + meth- + -prim (by shortening & alteration from pyrimidine)

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Time Traveler for trimethoprim

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The first known use of trimethoprim was in 1964

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Cite this Entry

“Trimethoprim.” Dictionary, Merriam-Webster, Accessed 2 Jul. 2020.

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tri·​meth·​o·​prim | \ trī-ˈmeth-ə-ˌprim How to pronounce trimethoprim (audio) \

Medical Definition of trimethoprim

: a synthetic antibacterial drug C14H18N4O3 used alone especially to treat urinary tract infections and Pneumocystis carinii pneumonia and in combination with sulfamethoxazole to treat these as well as other infections (as shigellosis or acute otitis media) — see bactrim

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