(Merck) Vetsulin (porcine insulin zinc suspension) is used to reduce hyperglycemia and hyperglycemia-associated clinical signs in dogs and cats with diabetes mellitus. The initial recommended dosage for dogs is 0.5 IU insulin/kg body weight once daily, given by SQ injection. Dosage may be adjusted, and twice daily therapy initiated in dogs, if necessary. The initial recommended dosage for cats is 1 to 2 IU insulin, given by SQ injection twice daily at 12 hour intervals. Vetsulin must be administered with a U-40 syringe (sold separately) to ensure accurate dosing. Porcine insulin zinc suspension, 40 IU/ml.