Skin Rash in Dogs

A skin rash can be painful, itchy and very uncomfortable.  Many skin conditions can quickly progress. The most common reason for skin rashes in dogs is allergies. Allergies may be caused by your dog’s diet, by the environment and by parasites. A few flea bites on a dog that is allergic to flea saliva can trigger itching and scratching for weeks.  A flea bite allergy is also known as 'flea allergy dermatitis'.

The most common food allergies in dogs are beef, dairy, chicken, corn, wheat, soy and yeast. A dog with a skin rash may also be reacting due to an allergy to the preservatives, dyes and fillers in his diet. Any dog can develop allergies. There are some breeds that are more prone to develop food and airborne allergies such as the Maltese, German Shepherd, Bull Terrier, Cocker Spaniel, American Hairless Terrier, Lhasa Apso, American Pit Bull Terrier, Golden Retriever and the English Bulldog.

Parasites not only cause skin rashes, but they can also rob your dog of nutrients. A heavy infestation of fleas, mites and ticks can also cause your dog to become anemic.

Dogs that have a skin rash should be seen by a veterinarian.  The veterinarian will be able to diagnose and treat the underlying reason for the skin rash.

Skin conditions are a very common health problem in dogs. A skin rash in dogs can be caused by an underlying condition such as parasites, bacterial infections and allergies.

Symptoms may include:

• Pimple-like pustules on the skin
• Hair loss
• Ulcerated skin
• Bleeding
• Red and inflamed skin
• Swelling
• Itchiness
• Skin flaking
• Weeping skin
• Constant licking, biting and chewing
• Scabs and crusty skin
• Strong bad odor
• Depression
• Greasy fur
• Secondary skin infection

Skin rashes in dogs may be caused by:

• Parasites such as fleas, ticks and mites can cause skin rashes in dogs; many dogs are allergic to the saliva of fleas. Ticks not only irritate the dog’s skin, they can transmit diseases such as Lyme disease and Rocky Mountain spotted fever; ticks can also transmit these diseases to humans. The mite Demodex canis is the cause of demodectic mange; Demodex canis lives on the dog’s hair follicles. Sarcoptic canine mange is caused by the Sarcoptes scabiei mite burrowing into the dog’s skin. 

• Atopic Dermatitis is common among pedigrees and tends to appear between the ages of one and five. Dogs can be reacting to food or their environment. Food allergies are the culprit in about 20% of atopic dogs. Environmental allergies such as grass, dust, mold, secondhand smoke, insecticides and cleaning chemicals can cause your pet to itch and develop a rash. Frustratingly, atopic dermatitis cannot be cured and tends to flare up repeatedly throughout a dog's lifetime.

• Heat rash is caused by the combination of staphylococcus bacteria and hot, humid weather; dogs with a thick coat are more susceptible to heat rashes. Hot spots are also referred to as 'acute moist dermatitis'. Hot spots can spread rapidly and a secondary staph infection can cause the skin to have open sores with pus. Hot spots occur more often in warmer weather.

• Skin Infections can be bacterial or fungal and can result in a red rash and associated lesions such as scabs and target lesions. They may be primary or secondary to an underlying issue.

• Contact Dermatitis is an over-reaction of the immune system and is the inflammation of the skin where it has been in contact with something. For example, a dog may develop a rash after being shampooed with a shampoo they have reacted to.

• An immediate allergic reaction can cause a rash and urticaria (raised hives). This may occur after e.g. a wasp sting and prompt veterinary attention is advised.

The veterinarian will want to go over your companion’s medical history.  He will want to know when the skin rash started and if you have noticed any other symptoms. The veterinarian will perform a thorough physical examination and may recommend a complete blood count (CBC).  A complete blood count can help determine if the dog has a bacterial infection or if he is anemic. A skin scrape or biopsy may be taken to be analyzed under a microscope. This can indicate the presence of parasites or secondary infections, such as a yeast overgrowth.

Mange is usually treated with dips and medicated shampoo.  Fleas and ticks are treated with a topical product and followed by regular application moving forward, of a parasite preventative medication. If your dog was diagnosed with parasites, the home and yard may need to be professionally fumigated.  Your dog’s bedding and toys should be washed in hot water and in-contact animals should be treated too.  

Dogs diagnosed with food allergies may need to have a dietary elimination trial.  An elimination diet, under the guidance of your veterinarian, can help determine what foods your dog is allergic to. Once a food sensitivity is identified, the rash caused by the reaction should begin to clear. Ointments to soothe the skin can be prescribed in the meantime.

The veterinarian may recommend you take your dog to a veterinary allergy specialist.  The allergist may recommend blood allergy testing and intradermal allergy testing to narrow down the environmental allergens.  In some cases, allergy shots (immunotherapy) can dampen or eliminate the allergic reaction.

 Heat rashes may be treated with calamine lotion or hydrocortisone cream. Dogs with hot spots may be prescribed antibiotics and a short course of corticosteroids. The hair around hot spots must be clipped away and topical medications will be prescribed.

Your dog will need follow up visits to help monitor his progress. Most dogs recover from skin rashes once the underlying condition is diagnosed and treated. However, even though a rash appears to be healed, the medication prescribed must be completed in full. The rash and itching may return otherwise.

It is worth noting that those who suffer with atopic dermatitis tend to experience rashes and itching that comes and goes. The aim is to manage these dogs as, unfortunately, it is rarely possible to 'cure' the disease.

Skin rash can be expensive to treat. If you suspect your dog has skin rash or is at risk, start searching for pet insurance today. Brought to you by Pet Insurer, Wag! Wellness lets pet parents compare insurance plans from leading companies like PetPlan and Trupanion. Find the “pawfect” plan for your pet in just a few clicks!

Curious about which health plan is right for your dog? Head over to our breakdown of the best pet insurance plans.