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How to Handle Vaccine Reactions in Cats & Dogs

A certain amount of risk comes with any veterinary medical procedure. However, in most cases, the benefits far outweigh the risks when it comes to vaccinations. In this post, our Kent vets list some common reactions cats and dogs have to vaccines, as well as actions to take if your pet reacts to their shots. 

Why should I have my pet vaccinated?

Vaccinations are a critical tool we use to help prevent cats and dogs from contracting serious contagious diseases that can jeopardize their long-term health. Vaccinating your pet typically outweighs the risk of your cat or dog having an adverse reaction to a vaccine. However, some animals do react to vaccinations. 

How many pets have serious reactions to vaccines?

Veterinary medical procedures, including vaccinations, always carry some inherent risks. However, the risk that your dog or cat will have a severe reaction to vaccines is very small. Nonetheless, for a pet parent whose pet does react, this can be a very distressing experience. 

What kinds of side effects can cats and dogs experience due to vaccinations?

When they do occur, most vaccine reactions in pets are mild, short-lived, and far less dangerous to your pet's life and well-being than the illnesses that vaccines protect against. Some common reactions that cats and dogs have to vaccinations include:

Lethargy & Slight Fever 

Lethargy, a slight fever and mild discomfort are among the most common reactions pets have to vaccines. You may notice your cat acting strangely after a vaccination or just not acting like their usually energetic selves. You may see your dog having trouble walking after the shots. This is a normal reaction to vaccinations, and signs or symptoms should be mild and only last one or two days. If your dog or cat isn't back to their regular selves within a couple of days, contact your vet for advice. 

Localized Swelling 

Vaccination-induced lumps and bumps are common in both dogs and cats. Frequently, a small, firm bump will form where the needle pierced the skin. This is a normal reaction, but pet parents should keep an eye on the bump to make sure it doesn't get bigger or show signs of inflammation, infection, or oozing. The lump should not be painful and will fade away over about a week. Contact your veterinarian if the lump appears to be infected or if it hasn't gone away after a week.

Sneezing & Cold-Like Symptoms 

While the majority of vaccines for dogs and cats are given via injection, some are given via drops or sprays into the pet's nose or eyes. Intranasal vaccine reactions resemble a cold, with symptoms such as a runny nose, coughing, and sneezing. Within a day or two, your pet should be free of these symptoms. Contact your veterinarian if your dog or cat does not recover within a few days or has more severe symptoms.

What serious reactions could my cat or dog have to vaccines?

Most reactions associated with vaccines are short-lived and mild but, in a few rare cases, more severe reactions requiring immediate medical attention can occur.

Symptoms of a serious reaction usually appear shortly after the vaccine is administered, but they can take up to 48 hours to appear. Facial swelling, vomiting, hives, itchiness, diarrhea, and breathing difficulties are all signs of a more severe vaccination reaction.

The most severe allergic reaction that pets can have to vaccinations is anaphylaxis. Anaphylaxis in dogs and cats usually occurs shortly after the vaccination, but it's important to remember that anaphylaxis can occur up to 48 hours after the vaccination.

If your pet shows symptoms of anaphylaxis following their vaccinations, call your vet immediately or contact your nearest emergency veterinary clinic.

How can I prevent my pet from reacting to getting their shots?

Vaccines play an essential role in protecting your pet's overall health. The risk of your cat or dog having a serious reaction to a vaccine is very low. 

If your pet has had a reaction to vaccines in the past, be sure to let your vet know. Your veterinarian may recommend that you skip a particular vaccination in the future.

When multiple vaccinations are given at the same time to smaller dogs, the risk of a vaccine reaction is increased. If your dog is a small or miniature breed, your veterinarian may recommend getting his or her shots spread out over several days rather than all at once.

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.

Is your pet due for their annual vaccinations? Contact our Kent animal hospital today to book an appointment for your cat or dog.

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