• Why do some pets get vaccine reactions? What are the symptoms?

    It is important to understand that vaccine reactions are most often due to an individual cat’s or dog’s sensitivity to the vaccine, not because the vaccination is bad or administered improperly. As an example, think of bee stings in people. While most people find stings unpleasant, they are not dangerous. But for people who are particularly sensitive, a bee sting can be life-threatening.

    What are the symptoms for a pet with a negative vaccine reaction?

    Although relatively rare due to pre-treatment blood work testing, vaccination reactions can occur. The most common symptoms are similar to those in people, including:

    Soreness at the injection site
    Mild lethargy
    General malaise (not quite feeling up to par)

    These types of reactions usually resolve themselves within 24 hours. However, in more serious case, some vaccine reactions may require an emergency trip to your veterinarian.

    Another known vaccine reaction can cause hives and swelling of the face, most noticeable around the eyes, which may appear almost shut. It usually occurs a few to several hours after being vaccinated. Dogs and cats that suffer from this kind of reaction are usually panting and agitated, because they are very itchy and uncomfortable.

    The biggest concern for pet owners is that the dog may be having trouble breathing. This is rarely the case but a logical conclusion because of the swelling, panting and general agitation. While these reactions are relatively easy to treat, respond well and resolve fairly quickly, if your pet experiences a reaction like this, we recommend that you bring your pet to your local veterinarian as soon as possible.

    Anaphylactic vaccine reactions

    The most serious and rarest of vaccine reactions is anaphylaxis. Pets who experience anaphylactic reactions usually do so almost immediately following the vaccination often while still in the veterinarian's office. These reactions are potentially life-threatening and must be treated immediately and aggressively.

    These pets usually vomit repeatedly, experience diarrhea which is often bloody and collapse, sometimes experiencing cardiac arrest. Most pets will recover with appropriate treatment.

    Again, these are very rare occurrences, which unfortunately cannot be predicted. However, you can rest assured that our veterinary team is skilled and fully prepared to handle a range of reactions should the need arise.


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