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Common Reactions to Vaccines in Dogs

Common Reactions to Vaccines in Dogs

Vaccinations help to protect your dog against a number of serious illnesses and diseases. However, owners may be concerned about the risk of adverse vaccine reactions that come along with their pup getting its shots. Here, our Lebanon vets explain the most common reactions found in dogs to vaccines and what to do if your dog has a reaction.

Why are vaccines recommended for dogs?

Annual vaccinations are critically important to preventing your pet from contracting serious contagious diseases that may threaten the long-term health and well-being of your poocj. Generally speaking, the benefits of having your dog vaccinated far outweigh the risks of your pup having a reaction to those vaccines. With that being said, some dogs do have negative health reactions to getting their shots.

Common Reactions to Vaccines in Dogs

it can be really upsetting to see your pet have an adverse health reaction to vaccines. Nonetheless, it's important for loving pet owners to remember that most reactions are mild, short-lived and generally far less dangerous than the illnesses the vaccines themselves protect against.

Vaccination time can be made less stressful for you and your pet by understanding what the most common reactions to vaccines are in dogs, and what you should do if your dog has a reaction to getting their shots.


Mild discomfort, lethargy and a mild fever are some of the most common reactions to vaccines in dogs. These common reactions are often characterized by your dog simply acting a bit odd (perhaps being a bit more tired and lazy than normal). This is a normal reaction to vaccinations in dogs and the symptoms should be mild and only last a day or two.

Lumps & Bumps

Lumps and bumps are a common reaction to vaccinations in dogs - especially around the injection site. After a vaccination, a small, firm bump may develop at the spot where the needle was injected into your pet's skin. This is a totally normal reaction. However, it's important to monitor these bumps to make sure they don't continue to grow or show signs of infection like inflammation, oozing pus, or become more sensitive as time goes on. 

The lump should gradually disappear over the course of about a week. If the lump shows signs of becoming infected, or hasn't disappeared after about a week, contact your veterinarian.

There is always a small chance of infection when the skin of an animal is punctured. Keep a close eye on the site where your dog got their injection. Watch for any signs of infection, since these can lead to far more serious conditions if not promptly treated. If you notice the spot where your dog had their injection is changing or becoming worrying, contact your vet as soon as possible. 

Sneezing & Cold Like Symptoms

Most of the vaccines recommended for dogs are given by injection however, the Bordetella bronchiseptica and parainfluenza virus vaccines are administered by drops or sprays into the dog's nose. Reactions to intranasal vaccines look much like a cold, and include symptoms such as a runny nose, coughing, and sneezing. Expect your dog to recover from these symptoms within a day or two. If your dog does not recover within a couple days, or has more severe symptoms, call your veterinarian.

Serious Reactions to Vaccinations

Reactions commonly associated with vaccines are usually short-lived and mild. That said, in a few cases, more severe reactions that need immediate medical attention may arise. These may be characterized by facial swelling, breathing, itchiness, diarrhea, and hives. Anaphylaxis (which more severe reactions to vaccines/ 

Typically, anaphylaxis will occur in dogs very shortly after their vaccine has been administered, but it's important to remember that this may occur up to 48 hours after their vaccine.

If your dog shows symptoms of anaphylaxis following their shots, call your vet immediately or contact your emergency veterinary clinic.

Preventing Reactions to Vaccines

Vaccines are essential in protecting your dog against a number of potentially fatal and contagious diseases. The risk of your dog having a serious reaction to a vaccine is very low. 

Be sure to let your vet know if your dog has a reaction to vaccines. Your vet may recommend that you to skip a particular vaccination in future.

The risk of reactions to vaccinations may be increased when multiple vaccines are given together, particularly in smaller dogs. Your vet may suggest getting your dog's shots over the course of several days rather than all at once, in order to help reduce your dog's risk of reacting to their vaccines.

Contact Cumberland Animal Hospital today to learn more about dog vaccinations and the possible aide-effects or reactions your pooch may have to their preventive care.

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Cumberland Animal Hospital is accepting new patients! Our experienced vets are passionate about the health of Lebanon companion animals. Get in touch today to book your pet's first appointment.

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