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    896 N. Burlington Boulevard, Burlington, WA 98233 US


  • The Chuckanut Valley Feline Center

    1214 Dupont Street, Bellingham, WA 98225 US


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Dog Behavior Change After Vaccination

Dog Behavior Change After Vaccination

After your pet gets their shots, you may often observe changes in their behavior. In this article, veterinarians in Burlington and Bellingham delve into the subject of dog behavior changes following vaccinations and address the typical worries of pet owners.

Vaccinations & Your Dog's Health

As a responsible pet owner, you should ensure your dog receives regular vaccinations. Vaccinations help protect your furry friend from serious and highly contagious diseases, playing a crucial role in your pet's annual preventive healthcare plan. They safeguard your dog's well-being by preventing potentially life-threatening illnesses.

While concerns about vaccine safety have arisen from time to time, our team of skilled veterinarians strongly believes that the benefits of vaccines in preserving the long-term health of most dogs outweigh any potential risks.

Here are some possible reasons for these behavior changes and why they might occur.

Common Behavior Changes After Vaccinations

Dogs often exhibit behavioral changes after getting their shots. Although these changes might appear concerning, it's crucial to note that they typically only last for a while and can differ from one dog to another. Here are some common behavior changes that pet owners might notice:

  • Decreased Appetite - Vaccinations can temporarily affect a dog's appetite. If your pet seems less interested in eating immediately after receiving shots, it is often nothing to be overly concerned about. Ensure they have access to fresh water and monitor their eating habits. If the reduced appetite persists for more than a day or two, consult your veterinarian.
  • Mild Discomfort - In some cases, dogs may experience mild discomfort or soreness at the injection site. They might exhibit signs of sensitivity when touched or may avoid putting weight on the affected leg, especially if the vaccine was administered in the leg region. This discomfort usually subsides within a few days.
  • Lethargy - Some dogs may experience lethargy or fatigue after vaccinations. This is a natural response as the body diverts energy to build an immune response. Allowing your dog time to rest and recover is crucial during this period.

Factors Influencing Behavioral Changes

Different factors can contribute to the behavioral changes you might observe in your dog following their vaccinations. It is essential to consider these factors when evaluating your dog's response to the vaccines they recently received:

  • Vaccine Components - Vaccines contain specific components, such as adjuvants or preservatives, to enhance their effectiveness and shelf life. In rare cases, dogs may exhibit allergic reactions to these components, leading to more pronounced behavioral changes. Discuss any concerns with your veterinarian to ensure the right vaccines are administered.
  • Stress and Anxiety - Veterinary visits, including vaccinations, can induce stress and anxiety in dogs. The anticipation of discomfort, strange environments, or unfamiliar people can trigger temporary changes in behavior. Comforting your dog with gentle reassurance and positive reinforcement can help alleviate stress during these visits.
  • Individual Sensitivity - Some dogs may be more susceptible to experiencing behavioral changes, while others may show no noticeable difference.

Can a dog start acting weird after rabies vaccination? 

Reactions to rabies vaccination in dogs are uncommon but can be severe. These reactions typically occur because the dog's immune system reacts strongly rather than due to any issue with the vaccine itself. Serious side effects usually manifest shortly after or within one to two hours of vaccination.

Rare reactions to the rabies vaccine may include:

  • Hives: Firm lumps that can appear all over the dog's body, which may or may not be itchy
  • Vomiting
  • Diarrhea
  • Swelling of the face, muzzle, and/or eyes
  • Severe pain or swelling at the injection site
  • Coughing
  • Collapsing or fainting

When to Seek Veterinary Advice

While most behavioral changes after vaccinations are normal and resolve within a few days, some situations may require veterinary attention. Contact your veterinarian if you notice any of the following:

  • Allergic Reactions - If your dog exhibits signs of an allergic reaction, such as excessive swelling, difficulty breathing, or vomiting, seek immediate veterinary care. Allergic reactions are rare but can be serious.
  • Uncharacteristic Behavior - If your dog displays unusual behavior unrelated to the common changes mentioned earlier, it is advisable to consult a veterinarian. They can help determine if the behavior is vaccine-related or stems from another health concern. 
  • Severe or Prolonged Behavior Changes - If your dog's behavior changes are severe, persist for an extended period, or worsen over time, consult your veterinarian. These changes could indicate an adverse reaction or an unrelated underlying issue.

Are Vaccines Right For Your Dog?

It is quite common for dogs to experience behavioral changes after vaccinations, which are usually harmless. By comprehending the purpose of vaccinations, staying mindful of potential behavior changes, and monitoring your dog's well-being, you can ensure a positive and healthy experience for your beloved companion.

If you have concerns about the safety of dog vaccinations, it is advisable to consult your veterinarian. They can evaluate your dog's general health, lifestyle, and risk factors, helping you make an informed decision about whether vaccinations are appropriate for your dog.

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.

Want to learn more about the benefits of having your dog vaccinated? Contact our Burlington and Bellingham vets today to book an appointment for your pet.

New Patients Welcome

Chuckanut Valley Vet Clinic and Chuckanut Feline Center is accepting new patients! Our experienced vets are passionate about the health of Burlington and Bellingham companion animals. Get in touch today to book your pet's first appointment.

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