Nitarsone is primarily used in veterinary medicine as an antiprotozoal agent, particularly in the treatment and prevention of histomoniasis (blackhead disease), a protozoal disease affecting poultry, especially turkeys. It is added to poultry feed to control the spread of the parasite Histomonas meleagridis, which causes significant economic losses in the poultry industry through necrotic enteritis and liver damage. Nitarsone helps reduce mortality rates and improve overall flock health. While it has also been noted for secondary growth-promoting effects, its primary role is disease control. However, as an organoarsenic compound, its use has been scrutinized due to concerns about arsenic residues in poultry products, potential human health risks, and environmental impact, leading to regulatory restrictions or bans in regions such as the United States and the European Union.