What reactions occur if a dog is allergic to a vaccine?

When a dog is allergic to a vaccine, it may show local skin redness, itching, raised temperature, and rash; a severe allergy may cause anaphylactic shock. Generally, vaccines are quite safe and do not easily cause allergic reactions.

If a dog shows allergic symptoms after vaccination, it may be allergic to an adjuvant in the vaccine or to the vaccine strain. If an allergic reaction is found, take the dog to a vet for desensitisation treatment promptly.