What Are The Side Effects Of Getting My Dog Vaccinated?

There are actually several types of vaccine reactions.

vaccine reactions in dogs

Certain vaccines are a must-have for your dog, but you might be wondering if there will be any side effects.

It’s possible for your dog to have a reaction to his vaccines — allergic or otherwise — but in most cases, these reactions aren’t super serious and don’t last very long.

The Dodo spoke with Dr. Clarissa B. Lyon, a veterinarian at Larklain Mobile Veterinary Services in Pennsylvania, to find out all about the different vaccine reactions in dogs and which side effects you should be concerned about.

Can dogs have an allergic reaction to a vaccine?

Dogs can have allergic reactions to vaccines, but the veterinary community doesn’t typically use the word “allergy” in these cases.

“We don't actually call it an allergy,” Dr. Lyon told The Dodo. “They can develop various hypersensitivities.”

The good news is that these reactions aren’t super common. “How often do they actually occur? Not very often,” Dr. Lyon said. But hypersensitivities can vary in seriousness, ranging from mild to, in rare cases, fatal.

“There are four main types of quote, ‘vaccine allergies,’ if you will. We prefer to call them hypersensitivities,” Dr. Lyon said.

According to the American Animal Hospital Association (AAHA), these types of hypersensitivities can cause specific symptoms, including:

  • Type 1 (aka acute anaphylaxis): can cause head and ear swelling, vomiting, hives, collapsing, shock and death
  • Type 2 (aka cytotoxic): can cause anemia and thrombocytopenia
  • Type 3 (aka immune-complex): can cause lesions and cloudy corneas
  • Type 4 (aka delayed-type hypersensitivity): can cause decreased immunity and mess with immune response (these reactions don’t typically happen for a while after your dog’s vaccination)

Other types of vaccine reactions in dogs

It’s important to note that not all types of vaccine reactions in dogs are because of hypersensitivities. Sometimes it’s just your pup’s body’s natural reaction to getting vaccinated.

“You're sore, you're achy, you might have a sore arm … that's not a hypersensitivity,” Dr. Lyon said. “That's not an allergy. That's just your immune system getting a POW.”

There are a bunch of other types of vaccine reactions your dog could have, including the following.

Injection site reactions

Injection site reactions to your dog’s vaccine can either be transient (aka temporary) or sustained (aka long-lasting).

According to the AAHA, transient injection site reactions include:

  • Pain
  • Swelling
  • Lumps you can see or feel

And for sustained injection site reactions, these could be things like:

  • Permanent hair loss
  • Skin discoloration
  • Granuloma (aka a mass of tissue)

Transient non-specific systemic effects

Transient non-specific systemic effects involve reactions that aren’t local to the injection site and can affect the whole body.

According to the AAHA, these effects include:

  • Lethargy
  • Anorexia
  • Fever
  • Overall soreness
  • Diarrhea
  • Vomiting
  • Seizures
  • Arthritis
  • Behavioral changes

Dog vaccine reaction treatment

Treatment for your dog’s vaccine reaction will vary based on the kind of reaction he’s having.

“Treatment will be based on what we think it's due to,” Dr. Lyon said.

If your pup’s having a serious hypersensitivity in response to a vaccine he received, that’s an emergency — so you’ll need to bring him to your vet or an animal hospital right away.

“If it's one of these acute-type ones where all of a sudden [the] face gets swollen, [your] dog can't breathe, they're collapsing … immediately take them to the emergency room or back to your primary veterinarian care,” Dr. Lyon said.

Milder symptoms, on the other hand, won’t need such intense treatment.

“​​For just lethargy, feeling achy, just kind of general soreness, we'll usually use a canine anti-inflammatory drug, something dispensed by your veterinarian,” Dr. Lyon said.

Remember, not all dogs have adverse reactions to their vaccines. But if your dog does develop a response to one of his shots, now you know what to expect and can determine the best course of action.