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METRONIDAZOLE AND PHENYTOIN

Medical Diagnosis and Drugs, Medications
A small and usually clinically unimportant rise in phenytoin levels may occur if
metronidazole is given with phenytoin, although a few patients have developed phenytoin toxicity. Fosphenytoin, a prodrug of phenytoin, may interact similarly.
This interaction is unlikely to be generally significant, but bear it in mind in case of an unexpected response to treatment. Indicators of phenytoin toxicity include blurred vision, nystagmus, ataxia or drowsiness.
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