Nizonide® 500 contains nitazoxanide, an antiparasitic agent with activity against several protozoan organisms. Its active metabolite, tizoxanide, interferes with metabolic pathways required for energy production in susceptible microorganisms.

Nitazoxanide is used primarily for treatment of intestinal protozoal infections, particularly diarrhea associated with Giardia lamblia (Giardia duodenalis) and Cryptosporidium parvum. Activity against additional microorganisms has been studied, but clinical use should follow established indications and physician assessment.

Treatment decisions, dosage, and duration should be determined by a qualified healthcare professional.