Allergic Reactions in Dogs After Immunizations

Your dog's veterinarian will assess his condition before giving him a vaccine.
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Thousands of dogs receive vaccinations from licensed veterinarians every year. Vaccines are designed to safely protect your canine companions from diseases and illnesses that can seriously impact their quality of life. Unfortunately, a small percentage of dogs are allergic to vaccines and will suffer an allergic reaction after being given their shots.

How Immunizations Work

Immunizations contain a small amount of a weakened or killed strain of the disease that you are trying to protect your pet against. Vaccines work by introducing a relatively harmless segment of the disease into your dog's body so that his immune system can react to it. When the immune system reacts to the disease, it will develop its own way to fight the illness and the resulting antibodies will protect your dog from catching the full version of the illness.

Your Dog and Immunizations

In most cases, your dog will respond normally to the vaccine and create antibodies without becoming noticeably ill. However, some dogs are allergic to vaccines. Dogs who are allergic to vaccines can suffer from an allergic reaction after the vaccine is given. Most allergic reactions are relatively minor but severe reactions do occur and can lead to death.

Vaccine Side Effects

The most common reactions your dog may experience after a vaccine include lethargy and minor swelling or soreness at the site of the injection. The American Veterinary Medical Association says most vaccine side effects will appear within a couple of hours of the initial vaccination and should disappear within 24 to 48 hours.

Allergic Reactions

If your dog suffers an allergic reaction to a vaccine, you will need to take him back to the veterinarian immediately. Symptoms of an allergic reaction to a vaccine include swelling, hives, itching, difficulty breathing, loss of appetite, vomiting, diarrhea, shock and even death. Prompt veterinary treatment can minimize the severity as well as the long term consequences of your dog's allergic reaction.