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Vaccine Reactions in Dogs: Everything You Should Know

Vaccine Reactions in Dogs: Everything You Should Know

While vaccinations protect dogs against many serious illnesses, some owners worry about adverse reactions to vaccines. In this post, our Parrish vets list the most common reactions dogs have to vaccinations, and which actions to take if your dog has a reaction after receiving their shots.

Reactions to Dog Vaccinations

Ensuring your dog gets the appropriate vaccinations and booster shots is one of the most important things you can do to prevent several conditions and diseases, some of which are potentially life-threatening to your four-legged friend. However, you may be concerned about the risk of reactions to various vaccines. 

While side effects from dog vaccinations are relatively common, it's important to be able to recognize them when they do happen and understand what you should do, if anything. In this article, our vets will share common vaccine reactions in dogs. 

Will my dog need every vaccine that's available? 

Your dog's risk factors for reactions will depend on their breed, age, and lifestyle. Your veterinarian can help determine these factors and advise which shots your pooch should have and when. 

What are the most common side effects of dog vaccinations? 

Any time your dog has a medical procedure - including coming in for vaccines - there's a chance they may have an adverse reaction. While seeing your dog in the midst of a reaction to a shot can be concerning, and even shocking depending on severity, side effects are typically short-lived and mild. 

Understanding what's happening and which actions to take if you see signs of a reaction to a vaccine in your dog can help keep both of you calmer while they get their shots and as they recover. Here are some common side effects from dog vaccinations: 


Lethargy and general feelings of discomfort are by far the most common reaction dogs tend to experience after receiving an injection. They may also have a mild fever. While many people would describe these experiences as feeling 'off', if your dog is lethargic after getting shots at your local vet clinic, this is actually a signal that your pooch's immune symptoms is responding well to the vaccine. 

These mild symptoms are normal and usually only last for 24-48 hours. If you notice that your dog isn't back to himself within this time frame, contact your vet. 

Lumps & Bumps

Lumps and bumps are other fairly common vaccine reactions in dogs. You may see a small, firm bump appear near the injection site after your pup's vaccination. Rest assured there's no need for concern - while the site may feel somewhat tender, this is simply your dog's immune system attempting to counteract irritation in the area. 

However, there is a risk of infection any time skin is punctured, so look over the injection site closely for signs of discharge, redness, swelling, or pain. 

Untreated infections may lead to more serious health concerns. If the area continues to redden, become irritated or swell, call your vet. 

Sneezing & Cold-Like Symptoms 

Though your vet will inject most of the vaccines your dog will need, vaccines for Bordetella bronchiseptica and parainfluenza viruses are administered in the form of sprays or drops in the dog's nose.

These vaccines may trigger cold-like reactions, which may include coughing, runny nose, and sneezing. Most pups will recover from these symptoms within one or two days. However, if your dog is showing more severe signs of a reaction, get in touch with your vet. 

Having Trouble Walking After Shots

The injection site may be painful or swollen after your pooch receives their shots. Therefore, you might see some limping and paralysis. Rear (posterior) end paralysis - a condition most common in dogs that have had a Rabies shot - mean that a dog's hind or back legs cease functioning as a result of a reaction. 

As unnerving as this sounds, the paralysis is not permanent and will probably improve on the tenth day after symptoms first appear. If your dog is having trouble walking after getting his shots, monitor any paralysis or limping symptoms closely and ask your vet for advice. 

Yelping or Crying After Vaccination

You might feel concerned if your puppy is yelping when you pick him or her up after their vaccination. Your instinct may be to ask your vet, 'Why is my puppy crying when I pick him up after his shots?'

However, this reaction is also natural and not something to worry about. Yelping will usually stop in a few hours, or a day or two at the most. If your puppy is still yelping beyond the 48-hour timeframe, contact your vet. 

Serious Reactions to Vaccines

Most vaccine-related reactions are mild and short-lived, however in rare cases severe reactions do happen and will require immediate medical treatment. Anaphylaxis is one such severe reaction and can lead to itchiness, swelling in the face, vomiting, diarrhea, hives and difficulty breathing. If any of the symptoms above appear in your dog, contact your vet or your nearest emergency veterinary clinic immediately. 

Can I prevent my dog from having a reaction?

Remember that your dog's risk of having a serious reaction to vaccines is very low. Notify your veterinarian if your dog has previously experienced side effects from vaccinations - he or she may recommend skipping a specific vaccine in the future. 

Particularly for smaller breed dogs, risk of vaccine reactions increases somewhat when multiple vaccinations are administered on one day. To help reduce risk of reaction for your dog, your vet may recommend scheduling your dog's shots over the course of several days. 

Note: The advice provided in this post is intended for informational purposes and does not constitute medical advice regarding pets. For an accurate diagnosis of your pet's condition, please make an appointment with your vet.

Are you looking for more information about dog vaccinations, side effects and preventive healthcare? Contact our Parrish vets to schedule an appointment.

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