The objectives of this study are to determine the pharmacokinetics and assess safety and efficacy of nitazoxanide in patients with AIDS-related cryptosporidial diarrhea, and determine steady state concentrations of nitazoxanide following repeated dosing. Another objective is to assess the relationship between malabsorption, as determined by the d-xylose absorption test, nitazoxanide blood levels, and efficacy. Progress report and summary of findings: No new subjects were enrolled during this period. Three subjects originally enrolled in the Phase I/II study who continued NTZ therapy on a compassionate maintenance basis were followed and remained improved. Results continue to be analyzed.