Nitazoxanide 500 mg is an antiparasitic medicine commonly prescribed to treat certain intestinal infections caused by parasites, including Giardia and Cryptosporidium. It works by interfering with energy production in susceptible organisms, helping the body clear the infection. If you are looking to buy nitazoxanide 500 mg online, purchase it only from a reputable, licensed pharmacy and follow local prescription requirements. The appropriate dose and treatment duration depend on the infection, age, and medical history. Common side effects may include nausea, abdominal discomfort, headache, or changes in urine color.