For a veterinary product labeled for use in multiple species, the limit should be based on the maximum product dose used on the smallest species. If the label indicates that the product may be used on juvenile and adult animals, the juvenile is considered the worst case. If the weight of the animal is required to calculate the dose, firms should use an average weight for that species. For a listing of some average animal weights, see the FDA draft guidance for industry on Waivers of In Vivo Demonstration of Bioequivalence of Animal Drugs in Soluble Powder Oral Dosage Form Products and Type A Medicated Articles. For animal weights not listed in that guidance, please contact FDA’s Center for Veterinary Medicine.
