Jeffery W H, Zelicoff A P, Hardy W R
Drug Intell Clin Pharm. 1982 Feb;16(2):157-9. doi: 10.1177/106002808201600212.
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 cell defect or were exposed to other oxidizing substances. One of the major metabolites of phenazopyridine is aniline, a known cause of methemoglobinemia. Aniline-induced methemoglobinemia is less responsive to treatment with methylene blue than nitrate- or nitrite-induced methemoglobinemia. This may explain, in part, the poor response to methylene blue by one of our patients.
两名患者在接受非那吡啶治疗后出现了有症状的高铁血红蛋白血症和溶血性贫血。在常用剂量的非那吡啶治疗后，高铁血红蛋白血症似乎很少发生；非那吡啶相关的溶血性贫血在过量用药后以及常用剂量后均有报道。第一名患者出现高铁血红蛋白血症的表现以及第二名患者对亚甲蓝治疗的反应均不寻常，提示患者存在红细胞缺陷或接触了其他氧化物质。非那吡啶的主要代谢产物之一是苯胺，这是已知的高铁血红蛋白血症病因。苯胺诱导的高铁血红蛋白血症对亚甲蓝治疗的反应不如硝酸盐或亚硝酸盐诱导的高铁血红蛋白血症。这可能部分解释了我们其中一名患者对亚甲蓝反应不佳的原因。
