Skip to Main Content
Ask About Financing

Please ensure that your pet is either in a travel crate or on a leash before bringing them to their appointment.

Vaccine Reactions in Dogs: Everything You Should Know

Vaccine Reactions in Dogs: Everything You Should Know

Usually, vaccinating your dog is much safer and more beneficial than the chance of them having a reaction. Our Jackson vets list the most common reactions to dog vaccines in this post and explain what to do if your dog has a reaction.

Why should I get my dog vaccinated?

Ensure your dog's well-being by vaccinating them when they're young and keeping up with booster shots as they grow. Vaccines help prevent serious diseases like hepatitis, rabies, and parvovirus. When you vaccinate your dog early and keep their shots up to date as adults, you're giving them the best chance at a long and healthy life. 

These diseases can be server, especially in puppies, so it's better to prevent them with vaccines than to treat them later on. 

Does my dog need all the available vaccines?

Your vet will identify the risk factors your dog faces based on their breed, lifestyle, and age before advising you on which immunizations are appropriate for your dog. 

What are the most common reactions to vaccines in dogs?

All medical procedures have an inherent risk of adverse reactions, and vaccines are no different. While seeing your pet have a reaction to vaccines can be upsetting, it's essential to remember that most reactions are short-lived and mild. Understanding the signs of a reaction and what to do if your dog has a reaction can help to make vaccination time less stressful for both you and your dog. 


When dogs get their shots, they often feel tired and uncomfortable, which can be similar to us feeling "off" when we're not well. This is a sign that their immune system is responding well to the vaccine. A mild fever may accompany these.  

These mild symptoms are normal and will likely only last a day or two. If your dog is still feeling lethargic after their shots or isn't feeling and acting back to normal within a couple of days, contact your vet. 

Lumps & Bumps

Lumps and bumps can be common reactions to vaccinations in dogs. Following the vaccination, a small, firm bump may develop at the spot where the needle was injected into the skin or muscle, leaving the area somewhat tender. These bumps develop due to your dog's immune system rushing to resolve the localized irritation at the site. 

That said, any time the skin is punctured, there is a chance of infection. Be sure to keep an eye on the site where the injection was given. Look for signs of swelling, redness, discharge, and pain. If left untreated, infected areas may lead to more serious conditions. Contact your vet if you notice the area becoming increasingly red or showing any of the symptoms listed above.

Sneezing & Cold Like Symptoms

Unlike most vaccines that are given with a shot, the Bordetella bronchiseptica and parainfluenza virus vaccines are administered by drops or sprays into the dog's nose. Reactions to these vaccines can look much like a cold and include coughing, sneezing, and a runny nose. Usually, dogs get better in a day or two. But if your dog has every symptom or doesn't improve after a couple of days, it's important to contact your vet.

Trouble Walking

Your dog's injection site may be painful or swollen after they receive their shots. Therefore, you may notice some limping and paralysis. Rear (posterior) end paralysis - a condition most common in dogs that have had a Rabies shot - means 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

If your puppy is yelping when you pick him or her up after their vaccination, it's understandable to feel some concern. Your instinct may be to ask your vet, "Why is my puppy crying when I pick him up after his shots?"

This is also a natural reaction and not something to get too worried about. Yelping will usually stop in a few hours or a day or two at the most. Contact your vet if your puppy is still yelping beyond the 48-hour timeframe. 

Serious Reactions to Vaccinations

Most vaccine reactions are brief and not very serious. However, in rare cases, some can be server and need quick medical help. Anaphylaxis is a severe allergic reaction characterized by facial swelling, vomiting, hives, itchiness, diarrhea, and breathing difficulties. Anaphylaxis typically occurs very soon after the dog receives the injection but may occur up to 48 hours after the vaccine has been administered. If your dog shows any of the symptoms listed above, call your vet immediately or contact your emergency veterinary clinic.

Can I prevent my dog from having a reaction? 

Vaccines protect your dog's long-term health and are generally very safe. However, if your dog has reacted poorly to a vaccine before, tell your vet. They might recommend skipping certain vaccines to avoid future issues. 

That said, if your dog has had a previous reaction to a vaccine, it is important to inform your veterinarian. Your vet may advise you to skip particular dog vaccinations due to anticipated side effects in the future.

To minimize this, the risk of side effects from dog vaccinations increases somewhat when multiple vaccinations are given at one time. This can be particularly true in smaller dogs. To help reduce the risk of reactions, your vet may suggest getting your dog's shots over the course of several days rather than all at once.

To learn more about vaccinations and preventive healthcare for your dog, contact our Jackson vets today to book an appointment.

New Patients Welcome

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

Contact Us

(731) 664-6200 Contact