| Puppy series start age | 6 to 8 weeks |
| Number of DA2PP doses in series | 3 doses, spaced 3 to 4 weeks apart |
| Rabies vaccine timing | First dose at 14 to 16 weeks |
| Rabies vaccination | Legally required in most U.S. states |
| Core vaccine count | 4 (distemper, parvovirus, adenovirus, rabies) |
| Series completion age | Typically 16 weeks, with a booster at 12 to 16 months |
Core vaccines every puppy needs
Core vaccines are recommended for all puppies regardless of lifestyle or location, because the diseases they prevent are widespread, serious, or transmissible to humans. Your veterinarian will typically administer these as a series starting when a puppy is 6 to 8 weeks old.
Core vaccine
A vaccine recommended for all dogs regardless of lifestyle, because the disease it prevents is widespread, severe, or poses a public health risk.
Non-core vaccine
A vaccine given only to dogs with specific risk factors, such as geographic exposure, lifestyle, or frequent contact with other animals.
Maternal antibodies
Protective proteins a puppy receives from its mother through milk. They provide early immunity but gradually fade, which is why a vaccine series is needed rather than a single dose.
DA2PP (or DHPP)
A combination vaccine that protects against distemper, adenovirus (hepatitis), parvovirus, and parainfluenza in a single injection.
Booster
A follow-up dose of a vaccine given after the initial series to maintain or restore immunity over time.
The four core vaccines are:
- Distemper: A viral disease affecting the respiratory, gastrointestinal, and nervous systems. There is no cure, and it is often fatal in unvaccinated dogs.
- Parvovirus: A highly contagious virus that attacks the digestive tract and can kill puppies within days. It survives in the environment for months.
- Adenovirus (hepatitis): Causes infectious canine hepatitis, which can damage the liver and kidneys severely.
- Rabies: Fatal in nearly all mammals once symptoms appear. Vaccination is legally required in most U.S. states and is the only protection available.
Distemper, parvovirus, and adenovirus are usually combined into a single injection called the DA2PP or DHPP vaccine. This reduces the number of injections a puppy receives while covering multiple diseases at once.
The puppy vaccination schedule
Puppies are born with some antibodies from their mother, but those maternal antibodies fade between 6 and 16 weeks of age. Because they can interfere with vaccine response, puppies receive vaccines in a series rather than a single dose. The goal is to have at least one dose take effect after maternal antibodies drop.
| Puppy series start age | 6 to 8 weeks |
| Number of DA2PP doses in series | 3 doses, spaced 3 to 4 weeks apart |
| Rabies vaccine timing | First dose at 14 to 16 weeks |
| Rabies vaccination | Legally required in most U.S. states |
| Core vaccine count | 4 (distemper, parvovirus, adenovirus, rabies) |
| Series completion age | Typically 16 weeks, with a booster at 12 to 16 months |
A typical schedule looks like this:
| Age | Vaccines typically given |
|---|---|
| 6 to 8 weeks | DA2PP (first dose) |
| 10 to 12 weeks | DA2PP (second dose), Bordetella if applicable |
| 14 to 16 weeks | DA2PP (third dose), Rabies |
| 12 to 16 months | DA2PP booster, Rabies booster |
After the puppy series is complete, most core vaccines are given every one to three years in adulthood, depending on the vaccine type and your veterinarian's recommendation. Before your puppy's series is finished, limit contact with unvaccinated dogs and avoid areas where unknown dogs congregate. See our new puppy preparation checklist for guidance on scheduling that first vet visit early.
Non-core vaccines: when they apply
Non-core vaccines are given based on a puppy's specific risk factors, including where they live, how they interact with other animals, and whether they are boarded or groomed regularly.
Common non-core vaccines include:
- Bordetella bronchiseptica: Protects against kennel cough, a highly contagious respiratory infection. Recommended for dogs that visit dog parks, boarding facilities, groomers, or dog daycare.
- Leptospirosis: A bacterial infection spread through water or soil contaminated by infected wildlife urine. Relevant for dogs in rural areas or those with exposure to standing water. It can also infect humans.
- Lyme disease: Recommended in tick-heavy regions. It does not replace tick prevention; it works alongside it. See our overview on parasite prevention throughout the year for more on tick control.
- Canine influenza: Two strains (H3N2 and H3N8) circulate in the U.S. Vaccination is most useful for dogs with frequent social contact with other dogs.
Your veterinarian will assess your puppy's environment and lifestyle to determine which non-core vaccines make sense. There is no one-size-fits-all list.
What to expect after vaccination
Mild side effects are normal. A puppy may be tired or slightly sore at the injection site for a day or two after vaccination. A small, temporary lump at the injection site can also appear and usually resolves within a few weeks.
Less commonly, a puppy may experience a more significant reaction, including facial swelling, hives, vomiting, or difficulty breathing. These reactions typically occur within 30 to 60 minutes of vaccination. If you notice any of these signs, contact a veterinarian immediately.
Vaccination does not guarantee complete immunity in every individual animal. Factors such as maternal antibody interference, stress, or underlying illness can affect a puppy's immune response. That is why completing the full series matters, and why annual wellness exams allow your veterinarian to reassess whether booster schedules remain appropriate.
This article is for informational purposes only and is not a substitute for professional veterinary advice. Consult your veterinarian to determine the right vaccination schedule for your puppy.