sul·​fa·​meth·​ox·​a·​zole ˌsəl-fə-ˌme-ˈthäk-sə-ˌzōl How to pronounce sulfamethoxazole (audio)
: an antibacterial sulfonamide C10H11N3O3S used alone or in combination with trimethoprim (as in the treatment of urinary tract infections or acute otitis media)

Examples of sulfamethoxazole in a Sentence

Recent Examples on the Web Other choices, like nitrofurantoin, trimethoprim/sulfamethoxazole, or cephalexin, have more effectiveness with less risk of toxicity. Dr. Keith Roach, oregonlive, 13 Mar. 2023 Next came Macrobid, a combination treatment of trimethoprim and sulfamethoxazole. Natalie Ma, STAT, 31 Oct. 2021 Antibiotics are used to treat donovanosis, including azithromycin, doxycycline, ciprofloxacin, erythromycin and trimethoprim-sulfamethoxazole. Scott Gleeson, USA TODAY, 26 Oct. 2021 Laboratory testing found that 20 of these cases were resistant to common antibiotics such as chloramphenicol, streptomycin, sulfamethoxazole and tetracycline. Sandee Lamotte, CNN, 25 Aug. 2021 My pulmonary doctor didn’t tell me much except to put me on sulfamethoxazole drugs. Dr. Keith Roach, oregonlive, 1 July 2021 Treatment of nocardia of the lung in people with normal immune systems usually involves trimethoprim and sulfamethoxazole; since that seemed not to do well for you, minocycline is a reasonable option. Dr. Keith Roach, oregonlive, 1 July 2021 Seeing a doctor is important not only because the infection can be diagnosed by stool exams, but also because the parasite is treatable with trimethoprim-sulfamethoxazole, an antibiotic combination, according to Dr. Sears. Colleen Murphy,, 29 June 2021 The usual treatment is trimethoprim/sulfamethoxazole, an antibiotic combination. Sarah Jacoby, SELF, 9 July 2018

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'sulfamethoxazole.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


sulfa + methyl + oxazole, a compound C3H3NO (from International Scientific Vocabulary ox- + azole)

First Known Use

1960, in the meaning defined above

Time Traveler
The first known use of sulfamethoxazole was in 1960

Dictionary Entries Near sulfamethoxazole

Cite this Entry

“Sulfamethoxazole.” Dictionary, Merriam-Webster, Accessed 26 May. 2024.

Medical Definition


variants or chiefly British sulphamethoxazole
: an antibacterial sulfonamide C10H11N3O3S used alone (as in the treatment of urinary tract infections or prophylaxis against meningococcal meningitis) or in combination with trimethoprim (as in the treatment of Pneumocystis carinii pneumonia, shigellosis, acute otitis media, or urinary tract infections) see bactrim, septra
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