Bithionol is primarily used as an antiparasitic agent, especially in the treatment of parasitic infections such as fascioliasis (liver fluke infection) and other trematode infections in both humans and animals, though its use in humans is limited due to potential toxicity and the availability of safer alternatives. It works by disrupting the metabolic processes in parasites, leading to their death. In veterinary medicine, it has been widely applied to control lung flukes and gastrointestinal parasites in livestock such as cattle, sheep, and goats. Additionally, bithionol has shown antibacterial and antifungal properties, which have led to its use in some topical antiseptics and disinfectants. It has also been investigated for its potential in treating certain types of cancers due to its ability to induce apoptosis in tumor cells, although this application remains experimental. Furthermore, it is used in research for controlling parasites in aquatic environments.