Nitazoxanide is primarily used as an antiparasitic medication to treat infections caused by protozoa and helminths. It is effective against gastrointestinal infections, particularly those caused by Cryptosporidium parvum and Giardia lamblia, which are common causes of diarrhea in immunocompromised individuals and children. The drug works by interfering with the energy metabolism of the parasites, leading to their elimination from the body. Additionally, nitazoxanide has shown antiviral properties and has been explored for its potential use in treating viral infections, including influenza and hepatitis C. Its broad-spectrum activity and relatively low side effect profile make it a valuable option in both clinical and veterinary medicine for managing parasitic and certain viral infections.