The pharmacokinetics of nitrofurantoin and its related bioavailability.
The pharmacokinetics of nitrofurantoin and its related bioavailability.
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呋喃妥因的药代动力学及其相关的生物利用度。
DOI：
10.1159/000401065
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发表时间：
1978
期刊：
影响因子：
--
通讯作者：
J. D. Conklin
中科院分区：
文献类型：
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作者：
J. D. Conklin
呋喃妥因是一种尿路抗菌剂，其临床有效性取决于治疗药物剂量期间遇到的高尿药浓度。在这些条件下，通常只能发现较低的血液药物浓度。根据口服和静脉给药后测定的尿呋喃妥因排泄量，合适剂型的口服呋喃妥因吸收良好。体外测试不能准确反映呋喃妥因的生物利用度，其生物利用度受配方差异、药物粒径和剂型的影响。呋喃妥因很容易被吸收并迅速分布到大多数体液中。它通过胆汁和尿液迅速大量排出。除了肾小管中的活性药物分泌和胆道药物转运外，呋喃妥因跨体膜的转移是通过扩散发生的。呋喃妥因在全血或血浆中的消除半衰期较短。结合其主要途径的快速排泄，几乎没有证据表明呋喃妥因与血浆蛋白或组织有任何延长的结合。呋喃妥因吸收和消除所涉及的一级动力学最适合通过单室开放模型来描述。呋喃妥因原形经胆汁和尿液排泄以及酶降解是主要的消除方法。
Nitrofurantoin is a urinary tract antibacterial agent whose clinical effectiveness depends on the high urinary drug levels encountered during therapeutic drug dosage. Under these conditions, only low blood drug concentrations are usually found. On the basis of urinary nitrofurantoin excretion determined after oral and intravenous drug administration, orally administered nitrofurantoin in a suitable dosage form is well absorbed. In vitro testing does not accurately reflect nitrofurantoin bioavailability, which is affected by formulation differences, drug particle size, and dosage form. Nitrofurantoin is readily absorbed and quickly distributed into most body fluids. It is rapidly excreted in large amounts in bile and urine. With the exception of the active drug secretion in the kidney tubule and biliary drug transport, nitrofurantoin transfer across body membranes occurs by diffusion. Nitrofurantoin has a short elimination half-life in whole blood or plasma. In conjunction with its rapid excretion by the primary routes, there is little evidence for any prolonged binding of nitrofurantoin to either plasma proteins or tissues. The first-order kinetics involved in nitrofurantoin absorption and elimination is most appropriately described by a one-compartment open model. Biliary and urinary excretion of unchanged nitrofurantoin and enzymatic degradation are the primary means of elimination.