Dog Sick 4 Days After Vaccination? [The Good, the Bad, and the Ugly]

Zack Keithy, our author, is a certified veterinarian technician (UC Blue Ash) for over 6 years (contact him here). The articles written here are based on his expertise and experience, combined with a review by our expert vet reviewers including Dr M. Tarantino. Learn more about us here.

Knowing that vaccines protect your furry friends from harmful diseases always brings relief.

That’s why when my dog, Bella, received her routine vaccinations, I thought nothing of it. However, just four days later, she became lethargic and stopped eating.

In shock, I took her to the vet right away.

After some tests, the vet confirmed that Bella was experiencing an adverse reaction to the vaccine.

This experience left me wondering:

How common are adverse reactions to vaccines in dogs? Why is my dog sick 4 days after vaccination?

And what can pet owners do to prevent them?

In this post, you will provide insights on the topic of dogs becoming sick after vaccinations and how you can handle it.

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Why Should You Vaccinate Your Dog?

Why Should You Vaccinate Your Dog?

As a dog parent, I bet you want your pup to live healthily. 

And the first step to that end is to vaccinate them against deadly diseases.

Experts develop vaccines to stimulate your dog’s immune system, helping them fight harmful viruses and bacteria. 

Without vaccines, your dog is more susceptible to severe illnesses that can even be fatal.

I remember a fellow pup owner who chose not to vaccinate because she thought it was unnecessary.

Sadly, a few months later, her dog fell ill and is positive for parvovirus – a severe and often fatal disease that can be prevented with a simple vaccine.

It was too late to save her pup and the experience was truly heartbreaking. 

This incident highlights the importance of vaccinating your dog.

Here’s why your dog needs to receive shots:

  • Vaccination can prevent the spread of diseases.
  • Many states require vaccinating your dog against rabies by law.
  • Vaccinating your dog can be more cost-effective than treating illnesses.
  • Puppies need vaccinations to build immunity, starting at six to eight weeks old.

Don’t wait until it’s too late – speak to your vet today about vaccinating your furry friend.

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Thank you. The rest of the article continues below.

Short history of canine vaccines

Did you know the amazing advancements in protecting your furry friends from diseases? 

It started in the 1800s by Louis Pasteur. He developed the first canine vaccine to protect dogs against rabies. 

Since then, there have been tons of new vaccines which protect against various diseases like canine distemper and adenovirus.

You might think that they give vaccines yearly only but vets are now recommending a frequent vaccination schedule. 

Recent studies have shown that many vaccines protect for much longer than you thought! Pretty cool, right?

And it doesn’t stop there! Even though vaccines are already awesome, they’re continually improving and updating. 

For example, in the early 2000s, they developed a canine influenza vaccine. 

And today, it’s considered an essential vaccine for dogs at high risk of exposure, like those who frequent dog parks or boarding facilities.

Thanks to all these advancements, dogs live healthier lives. 

Doggy says, consider reading this too: Lepto vaccine for toy breeds

What Are the Side Effects of Vaccination in Dogs?

What Are the Side Effects of Vaccination in Dogs?

Vaccinations are necessary to keep your furry friends protected from deadly diseases but there can be side effects.

Here’s a rundown of the most common to serious side effects of vaccination in dogs:

Most common side effects

  • Lethargy
  • Soreness
  • Mild fever

Other mild side effects

  • Redness, pain, and tenderness at the vaccination site
  • Decreased activity levels and loss of appetite
  • Runny nose
  • Sneezing
  • Coughing

More serious but less common side effects

  • Allergic reactions
  • Persistent vomiting and diarrhea
  • Difficulty breathing
  • Severe coughing
  • Collapse, fainting, or inability to get up.

Side effects can occur, but they are quite rare, and the benefits of vaccination far outweigh the risks.

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Why is My Dog Sick 4 Days After Vaccination?

When your furry bestie gets shot, they might feel under the weather afterward but it’s totally normal!

Your dog’s immune system reacts to the shot’s ingredients and there is a small chance that they can become sick.

The good news is they are usually mild and disappear within a few days.

If your dog is experiencing symptoms of illness four days after vaccination, it could be due to a reaction to the vaccine, but it could also be due to an unrelated illness, so watch your pup’s health during this time to ensure they feel okay.

I should also remind you not to let your dog bathe right after vaccination. Its immune system is slightly out of whack now, so you don’t want to introduce any other shock to its body!

Why Do Vaccines Make Dogs Sick?

If your dog receives a vaccination, their immune system responds to the vaccine’s components. 

This immune response is necessary to safeguard the dog from potential exposure to the actual disease. 

But it can result in side effects.

Your dog’s immune system reacts locally and systemically to the vaccine administration. 

Locally, the immune response occurs at the injection site, like redness, swelling, and tenderness. 

And systemically, the immune system response can cause lethargy, soreness, and mild fever. 

How Long After a Vaccine Can a Reaction Occur in Dogs?

The timing of vaccine reactions in your dog can occur either immediately after the vaccine or within 48 hours of vaccination. 

It’s also common for your pet to develop a small, firm nodule at the vaccination site due to the body’s immune response, which should go away within 14 days.

But don’t worry too much, though. In most cases, your dog returns to their usual self within a day after vaccination. 

Are There Any Specific Vaccines That Increase the Risk of Vaccine Reactions in Dogs?

All vaccines increase the risk of adverse reactions, but they are generally safe and essential in protecting your furry friend from serious diseases. 

Vaccines contain a weakened version of the disease and it helps your dog’s immune system build up a resistance to it.

While most dogs respond well to vaccination, some do not due to genetics or previous health issues. 

So, knowing the potential risks associated with each vaccine is necessary.

The following are the risks of vaccine reactions in dogs:

  • Rabies vaccine

The rabies vaccine is the one most likely to cause a reaction in your pet.

Side effects of the vaccine are generally mild and it includes slight fever, a loss of appetite, and fatigue lasting 24 to 36 hours.

Serious side effects such as hives, vomiting, and diarrhea are really rare.

  • Distemper vaccine

The distemper vaccine is another vaccine that can cause a reaction in your pup.

Side effects include lethargy and soreness at the injection site.

These are usually mild but, if prolonged, can indicate a more severe problem.

  • Parvovirus vaccine

The parvovirus vaccine is another vaccine that can potentially cause a reaction and these include side effects such as lethargy and a mild fever. 

Can Vaccine Reactions in Dogs Be Prevented?

Preventing vaccine reactions in your dog may not always be possible. But some strategies can help minimize the risk.

Additionally, you can ask your vet about using titer tests to determine whether your dog needs certain vaccines.

Titer tests measure antibodies against a particular virus, which can help determine if a dog has already been adequately vaccinated against that virus and doesn’t need a shot.

Keep reading for some steps you can take to minimize the risk.

  • Discuss your pup’s medical history with your vet before vaccination. 

Health conditions can increase the risk of a vaccine reaction, so be sure to let your vet know about any underlying health issues your dog may have.

  • Follow the recommended vaccine schedule. 

Vaccines are typically given at specific ages or intervals to provide the best protection against diseases. 

That means that delaying or skipping vaccines can put your pet at risk for illness and increase the likelihood of a vaccine reaction.

  • Observe your dog closely after vaccination.

Watch for any unusual symptoms or changes in behavior, such as difficulty breathing, persistent vomiting, and diarrhea, and call your vet immediately if your pup shows any of these signs.

  • Consider splitting up vaccines. 

Some vets recommend splitting up vaccines into multiple appointments to minimize the risk of a vaccine reaction. 

I like this approach as it allows your dog’s immune system to handle the vaccine antigens better.

  • Use a high-quality vaccine. 

The truth is, not all vaccines are created equal.

To ensure you are getting the best treatment for your dog, I highly recommend that you work only with licensed and reputable vets to get the vaccinations.

They should know about the latest vaccine protocols and can provide you with up-to-date information.

How to Help Your Dog After Their Vaccination Shots?

Your furry friend has just received their vaccination shots, and you want to ensure they recover as smoothly as possible.

The following tips will help your dog feel better following vaccinations:

  • Keep an eye on them: Look for serious symptoms, such as allergic reactions, breathing problems, or a persistent cough. Call your vet if you see anything unusual.
  • Give them water: Vaccinations can sometimes cause dehydration, so make sure your dog has plenty of fresh water.
  • Let them rest: Allow your dog to take it easy for the day after their vaccinations. Don’t engage them in strenuous activities or playtime.
  • Check the injection site: Look for any signs of swelling, redness, or discharge. Contact your vet if you observe anything strange or if the swelling persists over a few days.
  • Keep them comfortable: Provide your dog with a soft bed or crate to rest in, and consider giving them a favorite toy or treat to help keep them comfortable and distracted.

Most dogs bounce back quickly from vaccinations and these simple steps will help your dog have a more comfortable and smoother recovery time.

When Should I See a Vet?

Again, I would emphasize that most dogs do not have any problems with vaccination shots, but of course, the unexpected sometimes happens.

Before you start panicking, I advise you to have a quick read through the following first:

After the shot, you should wait at the clinic for 30 to 60 minutes before bringing your pet home. This will give you some time to assess if he or she needs any further attention from the vet.

But when to take your dog to the vet after vaccination?

Look out for symptoms

After vaccinating your dog, watch it closely for unusual behavior.

Here are some signs you don’t want to see:

  • Persistent vomiting or diarrhea
  • Swelling of the face, neck, or eyes
  • Difficulty breathing or coughing
  • Persistent lethargy or weakness
  • Hives or severe itching
  • Seizures or collapse

How will my vet treat a vaccine reaction?

Just like how some people may react to a medication, vaccinations can sometimes cause reactions in our furry friends too.

To help you understand what to expect, here’s a breakdown of the treatments your vet may recommend:

For mild reaction

If your pet has a mild reaction, your vet may suggest simple home remedies such as rest, plenty of fluids, and closely monitoring their symptoms.

For moderate reaction

Your vet may prescribe medication like Aspirin or Tylenol for a moderate reaction. To alleviate symptoms such as pain, swelling, or fever. 

They may also give your pet fluids intravenously. To keep them hydrated and help support their organ function.

For severe reaction

In severe cases, hospitalization is necessary. If your pet has trouble breathing or experiences life-threatening allergic reactions. Your vet will provide emergency treatments like epinephrine, oxygen therapy, or corticosteroids.

Doggy says, you might be keen to read this too: Pros and cons of Lyme vaccine for dogs

Frequently Asked Questions (FAQs)

What dog breeds are susceptible to a vaccine reaction?

All dog breeds can have vaccine reactions, but some breeds, such as Chihuahuas, Pugs, and Dachshunds, are more prone to vaccine reactions due to a genetic predisposition. Watching your dog for any unusual symptoms after receiving a vaccine is always the best approach.

What are the side effects of the distemper vaccine in dogs?

Distemper vaccines may cause some side effects—including fever, lethargy, and loss of appetite. Some cases, severe side effects such as vomiting, diarrhea, and difficulty breathing may occur.

Does my dog need all the vaccinations that are available?

Not all dogs need all the vaccinations that are currently available. Your dog’s age, lifestyle, and risk of exposure to certain diseases will determine appropriate vaccinations. Consult your vet to determine the best vaccination plan.

Should I have my dog revaccinated?

Yes, revaccination for most vaccines ensures your dog remains protected. However, the frequency of revaccination may vary depending on the vaccine and your dog’s lifestyle. Consult with your vet on revaccination.

Can Lyme vaccine make a dog sick?

Lyme vaccine can cause some dogs to experience mild side effects such as lethargy, fever, and loss of appetite. In rare cases, more severe side effects may occur. Update your vet for any specific side effects of the Lyme vaccine.

What should I do if my puppy or dog vomits after getting vaccinated?

If your puppy or dog vomits after vaccination, contact your vet for instructions. They will recommend monitoring or giving medication to help with symptoms. It’s always better to be safe, so don’t hesitate to contact your vet if you have any concerns.

In Conclusion: Dog Sick 4 Days After Vaccination

Well, well, well, looks like your dog might be feeling a little ruff after his vaccination.

While it’s not the most paw-some experience, just know that vaccines are crucial for keeping our furry friends healthy.

If your pup is experiencing any symptoms after vaccination, don’t hesitate to reach out to your vet.

With their expert guidance and some TLC from you, your pup will be back to their tail-wagging self in no time!

Craving more pup-tastic tales? Check out these other articles too:

You’ve made it to the end, but I hope it’s not the end of our journey. We want to hear your voice! Share your thoughts, problems, suggestions, or anything related to your dog in the comments section. And don’t forget to join our newsletter today too.

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Zack Keithy
Zack Keithy

Hey, I'm Zack, the Chief Editor here. I was formerly a Certified Veterinary Technician (CVT) for a good 6 years before moving on to greener pastures. Right now, I am still heavily involved in dog parenting duties, and it is my desire to share all our knowledge with fellow dog owners out there! Connect with me on LinkedIn, or read more about Daily Dog Drama!

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