Vaccination - Please keep refrigerated. Provides protection against canine Distemper and Adenovirus Type 2. Modified live virus. Recommended for the vaccination of healthy dogs 42 days of age or older.Inject 1 dose (1 ml) subcutaneously into dogs. Because there is potential for maternal antibody to interfere with the immune response, revaccinate every 14 to 28 days until the dog is 16 weeks of age.Dogs over 16 weeks of age should receive a single dose (1 ml). Annual revaccination with one dose is recommended.