Sulfadimethoxine is a sulfonamide antibacterial used to treat many infections including treatment of respiratory, urinary tract, enteric, and soft tissue infections. It is most frequently used in veterinary medicine, although it is approved in some countries for use in humans. Sulfadimethoxine inhibits bacterial synthesis of folic acid (pteroylglutamic acid) from para-aminobenzoic acid. Sulfadimethoxine is approved in Russia for use in humans, including children, and has been successfully used there for more than 35 years and is available as an over-the-counter drug manufactured by a number of Russian pharmaceutical companies. In USA and Europe sulfadimethoxine is approved in a veterinary medicinal products. ANADA was approved by FDA in US in 1997 as an Over the Counter medicine for treatment of bovine respiratory disease complex (shipping fever complex) and bacterial pneumonia associated with Pasteurella Spp. Sensitive to sulfadimethoxine; necrotic pododermatitis (foot rot) and calf diphtheria caused by Fusobacterium necrophorum (Sphaerophorus necrophorus) sensitive to sulfadimethoxine. Bioequivalence for this generic animal drug, Sulfadimethoxine Injection 40%, was established by demonstration of chemical equivalence to the pioneer product, Hoffmann-La Roche's Albon® Injection 40% (NADA 041-245).