What is the Nitazoxanide medicine?   Nitazoxanide 500mg is used to treat diarrhea in adults and children older than 1 year of age caused by the protozoa Cryptosporidium or Giardia. Protozoa are suspected as the cause when diarrhea lasts more than 7 days. Nitazoxanide is in a class of medications called antiprotozoal agents.   Introduction of Nizonide 500 mg...