Diclazuril is primarily used as an anticoccidial agent in veterinary medicine, especially in poultry and livestock production. It effectively controls coccidiosis, a parasitic disease caused by protozoa of the genus Eimeria, which can lead to severe intestinal damage and reduced growth performance in birds such as chickens and turkeys. Administered through feed or drinking water, diclazuril helps prevent outbreaks in commercial poultry operations, improving feed efficiency and overall flock health. It is also used in aquaculture to combat certain protozoan infections in fish, contributing to better survival rates in farmed species. In addition, diclazuril has shown efficacy in treating and preventing toxoplasmosis in small animals and is being explored for use in companion animals and wildlife management. Due to its high potency at low doses and favorable safety profile, it is a valuable tool in integrated parasite control programs.