The most common cause of a dog skin rash is an allergic reaction. Allergies develop in dogs between 1 and 3 years of age. Dogs can be allergic to something they touch, inhale or ingest. A substance that causes an allergic reaction is known as an "allergen." Common canine allergens include foliage, synthetic materials (like nylon), natural materials (like wool and rubber), food, food additives, milk, dust, dust mites and flea bites.
Signs Your Dog Is Allergic to Something
The hallmark symptom of most canine allergies is "pruritus," or itching of the skin. Canine allergy symptoms may include:
- Chewing feet and tail
- Rubbing face against surfaces
- Scratching
- Skin mutilation
- Skin infection
Skin Rashes Associated with Canine Allergic Reactions
Allergic contact dermatitis, a rare condition, occurs when a dog reacts to environmental allergens, including antibiotic ointments, metals, rubber, wool, dyes, carpet deodorizers, among others. It is not to be confused with "irritant contact dermatitis," caused by contact with noxious chemicals.
Hives, or skin bumps, erupt when your dog reacts to medicines, chemicals, food and sunlight. Hives may accompany anaphylactic shock, which requires immediate medical attention.
Flea bite allergy occurs when a dog reacts to flea saliva. Dogs allergic to flea bites nip at their tail, scratch frequently, lose hair and develop hot spots.
Treatment of Canine Skin Allergies
To treat canine skin allergies, administer fatty acid supplements, antihistamines, biotin and topical shampoos as directed by your vet. Other helpful provisions include glass or stainless-steel bows; hypoallergenic detergents and shampoos; and an EpiPen® syringe used for life-threatening allergic reactions.