My friend who is traveling has been prescribed this by a doctor in Guatemala for treatment of amoebic dysentary. Is that what this drug is primarily used for? ## The medicine Nodik (branded outside the USA) is the active ingredient Nitazoxanide. It is marketed in the United States as Alinia. Nitazoxanide is an antiprotozoal agent. It is used to treat diarrhea in adults and children caused by the protozoa Giardia lamblia. Nitazoxanide is also used to treat diarrhea caused by the protozoa Cryptosporidium parvum. These conditions are also sometimes referred to as travelers' diarrhea. Stop taking nitazoxanide and seek emergency medical attention if you experience a rare allergic reaction (difficulty breathing; closing of the throat; swelling of the lips, tongue, or face; or hives). Othe...