amox·​i·​cil·​lin | \ə-ˌmäk-sē-ˈsi-lən \

Definition of amoxicillin 

: a semisynthetic penicillin C16H19N3O5S derived from ampicillin

Examples of amoxicillin in a Sentence

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Another example: when a child takes amoxicillin for an ear infection and has an upset stomach or superficial pink skin rash. Ronald S. Litman,, "Should I worry about my child being allergic to anesthesia?," 9 July 2018 Antibiotics commonly used for oral treatment include doxycycline, amoxicillin, or cefuroxime axetil. Kara Driscoll, ajc, "Lyme disease: 7 questions answered about tick-borne infections," 7 May 2018 The bacteria involved are resistant to not only methicillin but also amoxicillin, penicillin and oxycillin. Cathie Anderson, sacbee, "Influenza B surging as overall flu cases fall — and it's deadlier in kids, experts say | The Sacramento Bee," 19 Mar. 2018 Moxifish, for instance, contains amoxicillin, a type of penicillin. Maya Wei-haas, Smithsonian, "This Is Why Taking Fish Medicine Is Truly a Bad Idea," 16 Aug. 2017 Taking amoxicillin while suffering a viral infection such as mono, for instance, can cause the body to erupt in rashes, says Morgan. Maya Wei-haas, Smithsonian, "This Is Why Taking Fish Medicine Is Truly a Bad Idea," 16 Aug. 2017 In their search, a few other antibiotics were associated with contraceptive failure in three or more case reports, including: ampicillin, amoxicillin, griseofulvin, metronidazole, and tetracycline. Korin Miller, SELF, "Can Antibiotics Actually Make Your Birth Control Fail?," 27 July 2017 There were also increased risks for birth defects with the use of moxifloxacin, ofloxacin, erythromycin and penicillin V. The study found no increase in birth defects with the use of amoxicillin, nitrofurantoin or the cephalosporins. Nicholas Bakalar, New York Times, "Certain Antibiotics May Increase Risk of Birth Defects," 20 July 2017 Sonia Hernandez, 29, brought her sick 6-year-old son, now taking amoxicillin for the fever, irritation and inflammation that surfaced after escaping through the smoke, to wait with her outside the apartment. Ellie Silverman, Washington Post, "‘We have nothing left.’ Residents return to scene of Northwest apartment fire," 28 June 2017

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

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First Known Use of amoxicillin

1971, in the meaning defined above

History and Etymology for amoxicillin

amino + ox- + penicillin

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The first known use of amoxicillin was in 1971

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More Definitions for amoxicillin


variants: or British amoxycillin \ə-​ˌmäk-​sē-​ˈsil-​ən \

Medical Definition of amoxicillin 

: a semisynthetic penicillin C16H19N3O5S derived from ampicillin — see amoxil, augmentin, larotid, trimox

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