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Pet Vaccine Side Effects and What You Should Know

There is always a level of risk with any medical procedure performed in veterinary medicine, even with vaccinations. However, with most vaccines, the benefits greatly outweigh the risks. Today our Hoquiam vets discuss several common side effects cats and dogs can have from vaccines and what you should do if your pet has one.

Why should I vaccinate my pet?

Vaccinations are an important part of keeping your pet safe from getting serious contagious diseases that can threaten your pet's long-term health. Usually, the benefits of giving your cat or dog vaccinations greatly outweigh the risk of your furry friend experiencing side effects. However, some cats and dogs do react to their shots.

How many pets have serious side effects to vaccines?

There's always some inherent risks with veterinary medical procedures including vaccinations. Although, the risk of your pet having a serious reaction to vaccines is very low. However, it can be very distressing for pet parents whose beloved companion does experience a side effect.

Approximately 1-10 cats of every 10,000 vaccinated will experience a serious side effect where 13 out of 10,000 dogs will have a reaction from a vaccine. This means that out of those 10,000 between 9, 990 - 9,999 cats and 9,987 dogs sail through the process without any serious problems.

What kinds of side effects can pets have to their shots?

Most reactions that pets have to vaccines are mild, short-lived, and generally far less dangerous than the illnesses the vaccines protect them from. Below we have listed some of the most common side effects cats and dogs get from vaccinations:

Lethargy & Slight Fever

  • Lethargy, mild discomfort, and a slight fever are the most common side effects pets get from vaccines. These can be characterized by your cat or dog not acting like themselves. This is a normal side effect of vaccinations, and the symptoms are usually mild and only last one to two days. If your pet isn't acting normally after a couple of days, call your vet for advice.

Localized Swelling

  • Lumps and bumps are a common reaction to vaccinations in both dogs and cats. Often a small, firm bump will appear at the spot where the needle pierced the skin. This is a normal reaction however pet parents should keep an eye on the area to make sure the lump doesn't keep getting bigger or show signs of inflammation, infection or oozing. The lump shouldn't be painful and should gradually disappear over the course of about a week. If the bump shows signs of becoming infected, or hasn't gone away after a week, call your vet.

Sneezing & Cold Like Symptoms

  • Most of the vaccines recommended for cats and dogs are given by injection however, some are administered by drops or sprays into the pet's nose or eyes. Reactions to intranasal vaccines look a lot like a cold, and symptoms include runny nose, coughing, and sneezing. Expect your cat ot dog to recover within one or two days. If your pet doesn't recover within a couple days, or has more severe symptoms, contact your veterinarian.

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

Most reactions associated with vaccines are mild and short in duration but, there are a few rare cases where side effects are more severe and require immediate medical attention.

The serious side effects will usually occur very soon after the vaccine is given but can take up to 48 hours to appear. Signs of a more severe side effect to a dog or cat vaccination include facial swelling, vomiting, hives, itchiness, diarrhea, and breathing difficulties.

Anaphylaxis is the most severe side effect a puppy or kitten can have to a vaccination. Anaphylaxis will typically occur in dogs and cats very soon after the vaccination has been administered, but it's important to know that anaphylaxis can happen up to 48 hours after the vaccine has been administered.

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

How can I prevent my cat or dog from reacting to their shots?

Vaccines are essential in protecting your pet's overall health. There is a very low risk of your cat or dog having serious side effects to a vaccine. 

If your furry friend has experienced side effects to vaccines in the past, please let your vet know. Your veterinarian might suggest skipping a particular vaccination in future.

In smaller dogs the risk of having a reaction to vaccines is increased when multiple vaccinations are given at the same time. If your canine companion is a small or miniature breed dog, your vet could suggest getting your puppy's shots done over the course of several days rather than all at the same time.

Is your puppy or kitten do for their shots? Or is it time for your cat or dog's annual vaccinationsCall our Hoquiam office today to schedule an appointment.

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Raintree Veterinary Center is accepting new patients! Our experienced vets are passionate about the health of Hoquiam companion animals. Get in touch today to book your pet's first appointment.

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300 Myrtle St Hoquiam WA 98550 US


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