Can Puppy Shots Cause Them to Be Sleepy or Lethargic?

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Can Puppy Shots Cause Them to Be Sleepy or Lethargic?
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No one enjoys getting a shot, and usually, you'll be a little sore for a day or two after. The same is true of puppies getting their vaccines. Usually, your puppy will feel just fine. However, if your puppy is lethargic after shots, this could indicate your pup will need a little extra attention, and possibly a trip back to the vet.

Why vaccinate?

Vaccinating your puppy is an essential step in helping to keep her healthy. According to the Drake Center for Veterinary Care, vaccines help to prepare your puppy's immune system to fight off disease-causing organisms. Many of the diseases that you vaccinate for can be deadly, as well as highly expensive to treat. Vaccines prepare your puppy's immune system to recognize these threats and fight them off.

In many states, rabies vaccinations are required for pets. If you ever plan to board your dog, enroll him in a dog playgroup, compete in a show, or have him groomed, then your dog will probably be required to have received certain vaccines.


Common puppy vaccines

According to VCA Hospitals, your vet may recommend vaccines based on the prevalence of particular infections in your area. You and your vet will discuss diseases such as rabies, distemper, leptospirosis, and more, and your vet will probably recommend that your puppy receive a set of standard "core" vaccines that are recommended by the American Animal Hospital Association Canine Vaccine Task Force.

Core vaccines address canine distemper virus, canine parvovirus, canine adenovirus-2, and rabies virus.


"Non-core" vaccines are recommended based on your dog's exposure risk, and help to prevent diseases such as the distemper-measles virus, leptospira, borrelia burgdorferi infection (causes Lyme disease), canine parainfluenza virus, and kennel cough.

Many of the core vaccines are available in combinations that are administered with a single dose, which helps to reduce the number of shots that your puppy needs. However, if your puppy has a known allergy, then your vet may recommend that you separate the vaccines so as to not overwhelm your dog's system with multiple vaccines at one time.


Puppy lethargic after shots

The Drake Center for Veterinary Care explains that vaccines carry far more benefits than their risks and that while reactions to vaccines do occur, they're rare. Any medication or vaccine can cause side effects, and the same is true of puppy vaccines.

After a vaccination, your puppy may display some minor symptoms, such as a mild loss of appetite, pain or mild swelling around the injection site, and a mild fever. Usually, you can monitor these symptoms at home, though definitely call your vet and let him know that the issues are occurring. You may notice that your dog is lethargic after shots. Your puppy may be sleepy for a day but should be back to herself the next day.


More severe reactions to watch for include facial or paw swelling, hives, vomiting, diarrhea, difficulty breathing, and collapse. If you notice any of these symptoms, call your vet immediately and get your dog medical help. If your dog is acting weird after shots, or your puppy is significantly lethargic and not just sleepy, then it is important to get your puppy veterinary attention as soon as possible.

Your vet will often watch your puppy for a few minutes after giving her vaccines, just in case she does have an allergic reaction. However, reactions can also be delayed, so you may not see symptoms until a few hours after your puppy gets her shots.


Vaccination precautions

To keep your puppy as safe as possible, schedule his vaccinations for days when you can be home with him. Before the appointment, try to get a sense of how much time your puppy spends sleeping each day, so you can quickly identify if your puppy is lethargic after his shots.

If your puppy or dog ever does have a reaction to a vaccination, your vet may want to run a titer to determine your dog's immunity and gauge whether future doses of that vaccination are needed. In some cases, your vet may pre-treat your dog with an allergy medication before administering the vaccine, if it's needed.


Vaccines provide your puppy with valuable protection against life-threatening diseases. While the vaccines do carry the risk of an allergic reaction, that risk is minimal and most pets will never have a problem.

Always check with your veterinarian before changing your pet’s diet, medication, or physical activity routines. This information is not a substitute for a vet’s opinion.