Do Dogs Have Allergic Reactions to Shots?

Immunizations, also called vaccinations or shots, against diseases such as rabies, distemper and Lyme stimulate the immune system so your dog won't contract those diseases. Dogs can have allergic reactions to vaccines ranging from mild to life threatening.

  1. Mild Reaction

    • Mild reactions to vaccinations include pain and swelling at the injection site, sluggishness, loss of appetite and fever. The intranasal Bordetella vaccine may cause a mild cough. These symptoms shouldn't need treatment, according to Dr. Mark Thompson on PetPlace.com. Call your veterinarian if the symptoms last for more than 24 hours or if they worsen.

    Moderate Reaction

    • The most common adverse reaction to vaccinations is hives, which cause a swollen and red face and neck. This type of reaction will generally be very itchy, causing dogs to scratch themselves. Hives can progress to severe breathing difficulties, so dogs at this stage should be treated by a veterinarian. Give an oral antihistamine in the early stages to reduce swelling and itching.

    Severe Reaction

    • Symptoms that require immediate attention by a veterinarian include vomiting, diarrhea, trouble breathing, staggering, seizures or collapse. This stage is life threatening, and epinephrine should ideally be given within minutes, says Dr. Holly Nash of peteducation.com. Your veterinarian will also open your dog's airway and administer drugs, such as steroids, as necessary. Any dog that's had a bad reaction to vaccination should be monitored at a veterinarian's office for any future vaccinations.