Hives and a swollen face are typical are allergic reactions to drugs, chemicals, something eaten, or even sunlight. Facial swelling (angioedema) and hives (urticaria) generally develop within 20 minutes of being exposed to the allergen. In hives, small bumps occur within the skin. The hair will often stand up over these swellings. Sometimes, they itch. In angioedema, you will see swelling of the face, especially the muzzle and around the eyes. Sometimes, the swelling is so severe, the dog cannot open his eyes.

Most often, these types of allergic reactions are not life-threatening and will go away by themselves. Rarely, the swelling in angioedema can affect the throat and make breathing difficult. Antihistamines are generally the best treatment for angioedema and hives. If severe, steroids are sometimes given.

If your dog has hives or a swollen face, contact your veterinarian right away. A more severe allergic reaction, called anaphylaxis, is life-threatening, and requires immediate veterinary attention.

Allergic Reaction to a Vaccine

If your dog has ever had a reaction to a vaccine your veterinarian will probably administer an antihistamine prior to future vaccinations and have your dog remain in the office after the vaccination, in cause your pet has a reaction. In some cases, certain vaccines may be excluded from your dog’s vaccination regimen, or a different type of vaccine will be used.
If a dog has already had an allergic reaction to a vaccine or medication, be sure your current veterinarian knows and the information is placed in your dog’s medical record.

Giving Pets Medication

Allergic Reaction to a Insect Bite

If your dog has developed hives or a swollen face from an insect bite, you may want to discuss various options with your veterinarian. Your veterinarian may give you a prescription for an ‘epi-pen.’ An ‘epi-pen’ is a special syringe and needle filled with a single dose of epinephrine.

If your pet has an anaphylactic reaction or severe angioedema, inject the epinephrine using the ‘epi-pen’ and seek emergency veterinary assistance immediately. Be sure to take the ‘epi-pen’ with you on any trips or hikes.