The anaerobic metabolism of metronidazole forms N-(2-hydroxyethyl)-oxamic acid.

N-(2-hydroxyethyl)-oxamic acid is formed when metronidazole is reduced either chemically or by the action of the intestinal bacteria. When metronidazole, labeled with carbon-14 in the hydroxyethyl side chain, is administered by gavage to rats in doses of 200 mg/kg, an average of 1.4% of the administered radioactivity is recovered in the urine in the form of N-(2-hydroxyethyl)-oxamic acid. The presence of conjugated N-(2-hydroxyethyl)-oxamic acid in some samples was suggested by the detection of small additional amounts of the free acid after treatment of the urine with beta-glucuronidase. The metabolite is not found in the feces. In contrast N-(2-hydroxyethyl)-oxamic acid is not found in the urine or feces of germfree rats which receive metronidazole. Thus, the finding of N-(2-hydroxyethyl)-oxamic acid in the urine of rats which receive metronidazole appears to depend on the activity of the bacterial flora.

• Publication year

  1979

• Venue

  Journal of Pharmacology and Experimental Therapeutics

• Publication date

  1979-03-01

• Fields of study

  Medicine, Chemistry

• Identifiers
  DOI 10.1016/s0022-3565(25)31588-0PMID 430360
• External record

  Open on Semantic Scholar

• Source metadata

  Semantic Scholar, PubMed

• No claims are published for this paper.

• No concepts are published for this paper.

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