Absorption, distribution, metabolism, and excretion of furazolidone. A review of the literature

Systematic determination of profiles of absorption, distribution, metabolism, and excretion of drugs is standard in the pharmaceutical industry today, and powerful, precise, and specific analytical methods are available to carry out such studies. In the case of furazolidone, developed in the late 1940s, the data were obtained with less precise analytical procedures. This gave rise to the misconception that furazolidone is poorly absorbed and inactivated in the intestine. Newer techniques, such as chromatography and 14C studies, have helped to establish that the drug is indeed well absorbed. Levels of radiolabeled analyte measured in urine indicate that more than 65% of an oral dose is recovered in each animal species tested. Chromatographic methods indicate that little or no intact drug is recovered.