Tizoxanide is primarily known for its role as the active metabolite of nitazoxanide, a broad-spectrum antiparasitic and antiviral agent. It exhibits significant activity against a variety of anaerobic and microaerophilic protozoa, helminths, and certain bacterial species. It is widely used in the treatment of gastrointestinal infections caused by parasites such as *Giardia lamblia* and *Cryptosporidium parvum*, especially in immunocompromised patients. Beyond its antiparasitic effects, tizoxanide has demonstrated in vitro antiviral activity against a range of RNA and DNA viruses, including influenza, hepatitis B and C, and coronaviruses. Its mechanism involves interference with host cell pathways that viruses depend on for replication, particularly through modulation of cellular kinase signaling and the unfolded protein response. Due to its immunomodulatory and antiviral properties, tizoxanide is being investigated as a potential therapeutic agent in chronic viral infections and inflammatory conditions of the gut. Its ability to act on both infectious agents and host inflammatory responses makes it a candidate for repurposing in emerging infectious diseases.