Canine Immune Mediated Disease => Autoimmune Skin disease => Topic started by: Penel CIMDA moderator on February 22, 2012, 03:16:14 PM

Title: Treatments for autoimmune skin disease
Post by: Penel CIMDA moderator on February 22, 2012, 03:16:14 PM
Treatments for Autoimmune Skin Disease

Unlike systemic autoimmune diseases, there are several treatment options for autoimmune skin disease, these include, topical ointments, steroids (prednisolone), cytotoxic drugs, azathioprine and Atopica (cyclosporine) and a combination of tetracycline or doxycycline and  niacinamide (Vitamin B3) and ‘steroid sparing’ supplements such as essential fatty acids and natural Vitamin E in therapeutic doses.

If the use of steroids is appropriate, then the regime is the same as systemic autoimmune diseases, with or without a ‘combination’ drug.
A drug licensed only a few years ago for atopic dermatitis in the dog is Atopica (cyclosporine), an immune modulating antibiotic. Since being licensed it is becoming very widely used in veterinary treatments.  Atopica is effective for immune mediated skin disease, but it is a very expensive drug and the cost is often prohibitive. Administration of grapefruit juice two hours before cyclosporine, however, leads to a significant increase of its bioavailability and the dose, and consequently the cost, of cyclosporine can be significantly reduced. (Reference: Effect of Grapefruit Juice on the Pharmacokinetics of cyclosporine in dogs. Veterinary Record Feb 7, 2004). The most frequently observed undesirable effects are vomiting, mucoid or soft faeces and diarrhoea. They are mild and transient and generally do not require the cessation of the treatment. Other infrequent side effects include: anorexia, change of hair coat, red and swollen pinnae (external ear), muscle weakness or muscle cramps. These effects resolve spontaneously after treatment is stopped. This drug should not be given to dogs with hepatic or renal insufficiency and it is advised to check these functions before treatment starts.  Atopica will initially be given daily until a satisfactory clinical improvement is seen. This could take up to 4 weeks. Treatment should be stopped after 8 weeks if no improvement is seen.  Once the clinical signs of the disease are satisfactorily controlled, Atopica can then be given every other day, gradually extending to every 3-4 days if a maintenance dose is required. Atopica should not be given within two hours of food.  For further details see the reference to cyclosporine in treatments for inflammatory/systemic autoimmune disease.

There is a group of five antibiotics that go under the heading of ‘Tetracyclines’. Two of these, tetracycline and doxycycline are indicated for the treatment of immune mediated skin disease having anti-inflammatory and immunomodulating effects, and the ability to suppress antibody production. Either one can be used in combination with niacinamide (vitamin B3) for the treatment of immune mediated skin diseases. It is more commonly used, and seems to be especially successful, for the treatment of SLO. It should be noted that food or dairy products can reduce the amount of tetracycline absorbed by 50% or more.  To maximise bioavailability it is recommended to administer the drug two hours before or after food. Unlike tetracycline, doxycycline is not affected by food or dairy products to the same extent (no more than 20% reduction) and this is thought to be insignificant.

It takes 1-3 months before positive results are seen and treatment is likely to be continued for 6 months or more. Doxycycline or tetracycline with niacinamide seems to be a good treatment choice as it avoids the use of steroids and other stronger drugs.

Essential fatty acids and natural Vitamin E also play an active role in the treatment of skin diseases and should be included in any treatment regime. Chinese herbs are also thought to be beneficial, and biotin in the treatment of SLO. 

It is always worth trying other treatment options before using immunosuppressive doses of steroids and azathioprine, and very expensive drugs such as Atopica, however some skin disease, such as those in the pemphigus group may need more aggressive treatment.

Shampoos or ointments such as fuciderm and Protopic (tacrolimus) can be useful in the treatment of skin disease.  Protopic has been used successfully in the treatment of anal furunculosis.