Skin Conditions

This page is about skin conditions in dogs and some of the possible reasons for them.

The following information is intended to provide basic understanding of the most common underlying causes of itching
 and allergies in the canine species.

Itching and Allergies in Dogs

External parasites and allergies are the two groups that are known for causing chronic itching in dogs.

What are allergies?

Allergy is a state of hypersensitivity in which exposure to a harmless substance known as an allergen induces the body’s immune
system to “overreact”. While dogs rarely experience respiratory allergies, they more commonly experience the effects of allergic hypersensitivities as skin problems.  Though there are a variety of presentations, this can often be seen as redness and itching,
recurring skin or ear infections, and hair loss.

What are the Major Types of Allergies in Dogs?

Flea Allergy

Fleas are the most common external parasite of companion animals. When fleas bite, they inject a small amount of saliva into
the skin. Dogs can develop an allergic reaction to this saliva, which is much more severe and long lasting than a normal fleabite.
 Even one fleabite is enough to cause allergic dogs to be very itchy all over their bodies for days. The hot and humid environment
 and small flats are ideal for rapid breeding of fleas, and dogs with allergies need constant treatment of both themselves and their environment to prevent any flea bites. The ideal flea control program utilizes products that target the various stages of the flea
 life cycle, not only the adult fleas on the pet.

Some of the Flea Control Products Available

When using the above products, you should use a shampoo that is not detergent or soap based so as not to
 interfere with the effectiveness of the products.

Frontline Spray, Frontline Plus, and Frontline Top Spot

• Frontline Spray - Provides long lasting flea and tick control in a spray form. It kills up to a 100% of fleas in less than 24 hours.
  Continues killing fleas for an entire month or more. Remains "water-proof" for 30 days. For dogs and puppies 8 weeks of age
  and up. Approximately one to two pumps per pound of body weight will be required. One for short haired, two for long or
  dense coats.
   

• Frontline Plus - Not only kills adult fleas but breaks the flea cycle by effectively stopping the development of new fleas.
  Frontline plus also all stages of 4 major ticks, including the one that carries Lyme Disease. Continues killing fleas for an
  entire month or more. Remains "water-proof" for 30 days. For dogs and puppies 8 weeks of age and up.
   

• Frontline Top Spot - Apply once a month to give your pet flea and tick control. Remains "water-proof" for 30 days.
  For dogs and puppies 8 weeks of age and up.

Revolution

Just a spot once a month protects dogs from heartworms, fleas, and other harmful parasites. It also kills adult fleas and can
be used to treat sarcoptic mange, ear mites and ticks. It can be administered to puppies as young as 6 weeks old.

Advantage and K-9 Advantix

Advantage stops biting fleas fast. It starts to kills adult fleas within an hour after application, and within 12 hours, 98-100% of
 fleas are dead. Advantage is available for dogs and puppies 7 weeks and older. Advantage can be used monthly.

K-9 Advantix

Like Advantage, K-9 Advantix stops biting fleas fast. It is a once a month flea, tick and mosquito control for dogs and puppies
7 weeks of age and older.

Food Allergy

Some pets develop specific hypersensitivities to components of their diets.  The allergen usually is the protein source such as
chicken, beef, or pork, although carbohydrates such as corn, wheat, or soy or additives such as preservatives or dyes may
occasionally cause problems. Normally, the problem develops in young puppies, which are fed the same diet for a long
period. Remember changing brands of food may not solve the problem, since most commercial dog foods will use similar
mixes of proteins, for example chicken or lamb. In the short term, symptoms can be relieved with drugs, but in the long term
 changing to a diet without the cause of the allergy is essential. The diagnosis of food allergy requires the dog be put on a
strict diet that only contains ingredients that he/she has never eaten before. The prescription diet is normally fed for a period
of 10-16 weeks, and if the signs resolve, a challenge is performed by feeding the former diet and watching for a return of the
 itching. If this occurs, a diagnosis of food allergy is confirmed.

Atopic Dermatitis

Canine atopic dermatitis is the second most common form of skin allergy among dogs: an estimated 10% are affected. A
genetically inherited and normally lifelong disease, the first sign of atopic dermatitis usually occurs between 6 months to
3 years of age. Atopic dermatitis occurs when hypersensitive dogs come in contact with or inhale common allergens such as
house dust mites, pollens and molds, which then generate an allergic reaction. The main symptom of atopic dermatitis is
itching. Dogs will chew on their feet, rub their face on the carpet, and gnaw and scratch at their skin. These actions, in turn,
worsen skin inflammation, and cause lesions, hair loss and dry, flaky skin. Since several different skin diseases can cause
itching, your veterinarian will perform some diagnostic tests and treatment trials to exclude other diseases and get to a
final diagnosis of atopic dermatitis. Your veterinarian will need to prefrom some diagnostic tests to rule out other
types of skin diseases. Once the diagnosis of atopic dermatitis is confirmed, your veterinarian may also perform an
allergy test to pinpoint the exact cause of the allergy. There are two basic types of allergy testing. 1. A blood test that
checks for certain antibodies in a dog’s blood. 2. Intradermal testing, in which injections are made into the skin to determine
 which of the allergens may be causing the allergic reaction. Atopic dermatitis is a chronic disease often complicated by
concurrent infections. It may be possible to treat and manage it but there is no cure for it.
 
Treatment for Atopic Dermatitis:

Avoidance of the offending allergens is, theoretically, the best solution. This can be helpful for house dust mite allergies. To
reduce pollen exposure, use air-conditioning and air filters, avoid the outside in the early morning and late afternoon, wiping
 down with moist cloths after going outside and frequent bathing.

Steroids are extremely effective for relieving severe itching and inflammation. However, the drawback is that they can have many
 short- and long-term side effects on the dog. Topical steroids are safer than oral steroids.

Cyclosporine A is an immunosuppressive agent that can be used to treat atopic dermatitis. It is in oral form and has been proven
 highly effective in relieving symptoms. he major short-term side effects are gastro-intestinal upset.  The long-term safety is
not completely known.

Antihistamines may help control itching, especially in conjunction with other treatments. However, since dogs respond differently
 to different antihistamines, several types may have to be prescribed before an effective one is found. Your pet can take
 antihistamines for life. The only side effect usually seen is drowsiness.

Fatty acids are a “natural” product with some anti-inflammatory properties. They are used as feeding supplements and may
help improve the response to antihistamine therapy.

Topical therapy, consisting of shampoos, rinses and topical anti-itch solutions offer immediate but only short-term relief.
Because atopic skin is sensitive, only specially designed hypoallergenic shampoos should be used, and you should be sure
to rinse thoroughly.

Desensitization, also called immunotherapy, requires identifying the offending allergen. A series of shots (allergy vaccine injection)
 are then administered over a lengthy period of time to “desensitize” the dog to the offending allergen. When effective, this
therapy is a valid option; but unfortunately, not all dogs respond to it. Results may not be seen for 3-6 months.

The management of canine atopic dermatitis may require other products, such as antibiotics and antifungals to cure the concurrent infections. Moreover, it is essential to treat atopic dogs with vigorous flea control to prevent a possible allergy to fleas.

Unfortunately, there is no cure for allergy and it is usually a life-long problem.

Hyperadrenocorticism - Cushing's Disease

Cushing's disease results from the production of an excess of the hormone cortisol. One of the most common signs of Cushing's disease is a drastic increase in thirst which causes excessive water intake and urination. Other symptoms include an increase in
appetite, an enlarged "pot-belly" due to the enlarging of the liver and the abdomen muscles weakening, hair loss (not due to itching/scratching), lethargy/weakness, panting and sometimes recurrent infections. 

Without treatment most dogs will die within one or two years.  With treatment your pet's life can be prolonged, sometimes
 to a normal life-span. 

Before undertaking expensive drug therapy, there are two tests that should be completed. 1. The dog is injected with a
synthetic hormone which should cause the adrenal glands to react and produce more cortisol. The rise in cortisol is detected
 with a blood screen after a couple of hours. 2. Dexamethasone Suppression: a synthetic steroid that affects the adrenal gland,
 telling it to stop producing cortisol.

There are 3 types of Cushing's Disease, and treatments...

1. Iatrogenic Cushing's: Iatrogenic Cushing's Disease is caused by the frequent use of cortisol. The excess amount of cortisol
tells the adrenal glands that they can halt production of cortisol in the body, which causes them to decrease in size. The
treatment for Iatrogenic Cushing's Disease is a slow withdrawal of cortisol.

2. Adrenal Cortical Tumor: A tumor of the cortisol producing cells with cause an increase of cortisol production. Although there
 are two adrenal glands, the tumor is typically in one gland only, resulting in a large gland, and a small gland, both of abnormal
 sizes. This leads to one gland over-producing cortisol, and the other gland (without the tumor) under-producing cortisol.
Treatment for an Adrenal Cortical Tumor is surgical removal of the tumor and it's gland housing, along with supplemental
injections of cortical until the remaining gland is producing cortisol at a normal level.

3. Pituitary-Dependent Hyperadrenocorticism: Caused by microtumors inside the pituitary gland, Pituitary-Dependent Hyperadrenocorticism that cause the gland to produce excessive hormones, which in turn cause the adrenal glands to
produce too much cortisol. In cases of Pituitary-Dependent Hyperadrenocorticism both adrenal glands are abnormally
enlarged.There is no cure-all for Pituitary-Dependent Hyperadrenocorticism. Treatment of the symptoms is all that is
currently available.

Demodetic Mange

The Demodetic mange is caused by an external parasite (demodex mite) that is also present in low numbers on healthy
animals, including people. Demodetic mange is diagnosed by your veterinarian taking a skin scraping from one or more of
the affected areas and looking at the slide(s) under a microscope for abnormal amounts of the demodex mite. This type of
 mange is NOT contagious!

Whether or not a pet shows symptoms of this disease depends primarily on their immune status. Since there is no easy
test to determine immune status, it is impossible to predict which pets will get this disease, or how well a pet will heal if
it shows symptoms of demodex.

In most dogs, these mites never cause problems. However, in certain situations, such as an impaired immune system, intense
stress, or malnutrition, the mites can reproduce rapidly, causing symptoms that range from mild irritation and hair loss on a
small patch of skin to severe and widespread inflammation, secondary infection, and--in rare cases--a life-threatening
condition. Small patches of demodicosis often correct themselves over time, although treatment is usually recommended.

Minor cases of demodectic mange usually do not cause much itching but might cause pustules on the dog's skin, redness,
scaling, hair loss, or any combination of these. It most commonly appears first on the face, around the eyes, or at the
corners of the mouth, and on the forelimbs.

In the more severe form, hair loss can occur in patches all over the body and might be accompanied by crusting, pain,
enlarged lymph nodes, and deep skin infections.

Minor, localized cases are often treated with medicated shampoos. Demodetic mange with secondary infection is treated
 with antibiotics and medicated shampoos as well as parasiticidal agents.

Proper care, good hygiene, and the maintenance of good health will increase a pet's resistance to skin disease.
Canine mange mainly occurs on young animals which are undernourished and suffering from internal parasites.

Keeping your pet vaccinated, de-wormed, on heartworm prevention, on a well balanced pet food, spayed/neutered, and
clean and happy will help reduce the stressful factors which enable this hereditary, genetic disease from occurring as often.

Sarcoptic Mange

Sarcoptic mange commonly know as scabies, is caused by an external parasite that burrows deep into the skin. This mite likes
 to tunnel in the upper layers of the skin. It is contagious to other pets. It causes intense itchiness, especially affecting the ear
 margins, elbows, and face. People can pick up this disease from their pet and show symptoms of itching, but it goes away by
 itself in a short time and does not require treatment in most cases.

The diagnosis of this skin condition, like most skin conditions, can not be made by just looking at the dog. Your vet is the
only one who can tell you for sure if your dog has this or one of the other skin conditions such as ringworm, demodex,
and allergies.

Unlike demotetic mange, dogs with sarcoptic mange experience itching which results in constant scratching thus causing hair
 loss and damage to the skin. Although the lesions start on the thinly haired areas such as the ears, muzzle and around the
eyes, if let go the condition can spread over the entire body forming thick scabs.

Ivermectin seems to be the treatment of choice for sarcoptic mange. It is usually administered in two doses, two weeks
apart, and sometimes in conjunction with antibiotics and medicated baths for skin infections and itch relief. All pets in
 a household where a pet has been diagnosed with this disease should also be treated.

Hives (Urticaria) and Swelling of the Face (Angioedema)

Urticaria and angioedema are hypersensitivity (or allergic) reactions to drugs, chemicals, something eaten, or even sunlight.
In general, both urticaria and angioedema are not life-threatening and will go away by themselves. Rarely, the swelling in
angioedema can affect the throat and make breathing difficult.

In urticaria, small bumps occur within the skin. Often, the hair will stand up over these swellings. Sometimes, they itch.
In angioedema, we see swelling of the face, especially the muzzle and around the eyes. Sometimes, the swelling is so severe,
 the animal cannot open his eyes. Angioedema often results in itching. Angioedema and urticaria generally develop within
20 minutes of being exposed to the allergen (substance to which the animal is allergic).

Antihistamines are generally the best treatment for angioedema and urticaria. If severe, steroids are sometimes given.
If respiration is affected, epinephrine is administered.

In general, there is no way to predict which animals may develop urticaria or angioedema as a result of exposure to a
certain substance. If a pet has already had a reaction, such as angioedema, or hives, to a substance, the substance should
 be avoided.

If your pet has developed urticaria or angioedema 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.