Acquired Methemoglobinemia and Hemolytic Anemia after Usual Doses of Phenazopyridine

  title={Acquired Methemoglobinemia and Hemolytic Anemia after Usual Doses of Phenazopyridine},
  author={William H. Jeffery and Alan P. Zelicoff and William R. Hardy},
  booktitle={Drug intelligence \& clinical pharmacy},
Two patients developed symptomatic methemoglobinemia and hemolytic anemia after treatment with phenazopyridine. Methemoglobinemia appears to be a rare occurrence after commonly used doses of phenazopyridine; phenazopyridine-associated hemolytic anemia has been reported both after overdose and after usual doses. The presentation of methemoglobinemia in the first patient and the response to treatment with methylene blue in the second patient were unusual, suggesting that the patients had a red… 

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