Valnemulin hydrochloride is primarily used in veterinary medicine as an antibacterial agent, especially in swine and poultry. It is effective against a range of Gram-positive bacteria and some Gram-negative pathogens, including Mycoplasma species. It is commonly used to treat and control swine dysentery caused by Brachyspira hyodysenteriae and intestinal infections due to Lawsonia intracellularis, which leads to proliferative enteropathy. In poultry, it is used to manage chronic respiratory diseases associated with Mycoplasma gallisepticum and Mycoplasma synoviae. Due to its mode of action—binding to the 50S ribosomal subunit—it inhibits bacterial protein synthesis, making it effective in controlling infections that are difficult to treat with other antibiotics. Valnemulin is typically administered through feed or drinking water, allowing for mass treatment in livestock operations. Its use is generally restricted to specific production stages due to concerns about antimicrobial resistance and residue. It is not approved for use in animals intended for organic production or in some regions for food-producing animals, depending on regulatory guidelines.