Dogs and cats can be mildly to severely allergic to stings from bees, wasps and other stinging insects, vaccines, or medications.
Insect Bite Hypersensitivity:
Allergic reactions to insect bites and bee stings are very common in pets and can vary in severity. The most common clinical signs that you may observe in your pet are facial swelling, swelling at the site of the bite wound, hives or redness of the ears and skin. Animals that exhibit a more severe reaction may have vomiting, diarrhea, drooling and/or collapse. Reactions that appear mild at first may have the potential to progress, therefore require prompt evaluation by a veterinarian.
There are 3 types of reactions that can occur.
Mild: Minimal swelling or pain at the sting/ injection site. May or may not require treatment. Monitoring for worsening of the reaction is strongly advised.
Moderate: Swelling at the site and then development of hives and/or swelling around the eyes or face. Hives may be easiest seen on the tummy area or groin area (cats rarely develop hives but will act itchy and can have difficulty breathing). These reactions usually result in the animal rubbing and itching excessively. The earflaps will often become red and thickened. The reaction may occur immediately after the sting, or be delayed minutes to hours. Your veterinarian best treats these kinds of reactions with injections.
Severe: Following the inciting agent the pet vomits, has diarrhea, and has difficulty breathing or collapses. NOTE-Giving oral antihistamines in the acute, severe reactions is usually ineffective and can be dangerous.
These animals need to be transported to a veterinarian immediately. If not treated the vomiting and diarrhea can become bloody and result in a very severe life threatening condition.
Call Your Veterinarian or Animal Urgent Care at (760) 738-9600