Is there a best treatment for atopic (allergic) dermatitis? In the discussion of conventional treatments in this chapter and the natural therapies in chapter 5, I would like you to consider the following. I believe the “perfect” treatment for allergies should meet these criteria:
- The treatment should be the cost effective.
- The treatment should be easy for the owner to administer.
- The treatment must be safe for the pet.
- The treatment must have minimal or no short-and long-term side effects.
- The treatment should be ideally help control the cause of the problem, rather than just cover up the clinical signs of scratching.
No matter what approach you ultimately choose, it should meet as many of these conditions as possible to be of the most benefit to your pet. As you will soon see, complementary treatments fill most of these requirements whereas conventional medications do not and are rarely suitable as the long term treatment for most allergic dogs.
Along with the criteria for a perfect treatment, keep in mind that no type of treatment, conventional or complementary, should be administered on a long-term basis without a proper diagnosis. The following case is a classic example of failing to diagnose the disease and then administering an incorrect treatment.
CONVENTIONAL TREATMENTS
THE MOST COMMONLY prescribed conventional treatment for allergies is corticosteroids (steroids). The second most common is antihistamines. While these medications can be effective in controlling itching in allergic patients, they do nothing to correct or cure the underlying disorder. All too often they are prescribed for chronic, long-term control of allergies without searching safer alternatives. As a result, many pets suffer unnecessary side effects from these treatments and never seem to stop.
Conventional treatments can be used safely and effectively when needed to provide short-term relief from the itchiness that bothers so many allergic dogs.
Remember that atopic dermatitis is an inflammatory, uncomfortable condition. As a result, any approach you select should help minimize the inflammation and discomfort that causes your dog to scratch. Thinking holistically, you must also consider the overall health of the dog.
Some of our conventional treatments are potentially harmful to the pet when used as the sole long-term therapy for treating allergies. For example, many doctors choose long-term therapy with corticosteroids for pets with atopic dermatitis. While corticosteroids will relieve inflammation and itching, they do nothing try and help the immune system to counteract the allergies. And with the long-term side effects associated with corticosteroids this the long-term side effects associated with corticosteroids, this choice of treatment is too risky unless absolutely necessary. Although the dog will feel better for a while, the treatment is actually making his health worse.
The various drugs used in allergy treatment work at different stages to help decrease the production of the pro-inflammatory compounds. For example, corticosteroids work at two places in this biochemical pathway. They help inhibit the enzyme that is responsible for metabolizing the membrane phospholipids into arachidonic and eicosapentaenioc acids, and they inhibit the enzyme responsible for breaking down arachidonic acid into pro-inflammatory compounds.
Understanding Inflammation
Inflammation is caused by damage to the tissues and cells of the affected body part. When a tissue is inflamed, it exhibits any or all of the following signs: redness, pain, tenderness, swelling, and loss of function. See “A Closer Look (page87) for the biochemical mechanisms of inflammation.
Let’s take a look at the two most common classes of medications currently used to treat atopic dermatitis.
CORTICOSTEROIDS
CORTICOSTEROIDS, OR STEROIDS for short, are the first class of medication that comes to mind when thinking of treating the allergic dog. The reason steroids are used in the treatment of allergic dogs is that they work extremely well and very quickly. For most pets, the scratching, redness of the skin and inflammation are relieved within 24 hours of taking steroids.
While steroids can be used safely and intelligently in a holistic approach to help allergic pets, they are one of the most frequently used and abused drugs in veterinary and probably human medicine. It’s just too easy for doctors to reach for the magic “steroid shot” to treat symptoms, without diagnosing and treating the disease. As a result, pets are often incorrectly treated for months or years before someone says, “Enough. There must be a better way!”
Many holistic-minded people think that corticosteroids are horrible drugs that are to be avoided at all costs. That is far from the truth, however. When a diagnosis suggests a disease that is most correctly treated with corticosteroids, they are actually wonderful; drugs that often can be lifesaving. Steroids must be used correctly at the right dose, for the proper length of time, and in the right patient. The problem is that this is often not the case.
Due to their numerous short-term and long term side effects, they have no place in the management of pet with chronic allergies, except in the rarest of pets where no other treatment gives the animal relief and the alternative is euthanasia. However, rational short term use of corticosteroids (to quickly relieve inflammation and itching) can be part of holistic regimen for the allergic dog.
DURATION OF COMMONLY USED CORTICOSTEROIDS
The actual duration of a corticosteroid, meaning how long a dose exerts its effects in the body, defends upon a number of factors, including the specific formulation of the medication. For example, the acetate and acetonide formulations of corticosteroids are repositol, or very long acting, preparations that can acts for weeks and last in the body for several months. These preparations are overused in veterinary medicine and are the most harmful if used repeatedly.
Short acting: Duration 8-12 hours
Intermediate acting: Duration 12-36
- Prednisone
- Prednisolone
- Methylprednisolone
- Triamcinolone
Long acting: Duration longer than 36 hours
- Betamethasone
- Dexamethasone (Azium)
Due to the side effects, pets on long term corticosteroid therapy, as a rule, are not expected to live as long as if they were not on these medications. This is why it is so distressing to see pets with allergies sentenced to a shortened life of corticosteroid therapy when no other therapies have ever been tried. Sure, there are those very rare pets that do not respond to any conventional treatment or complementary therapy so must take corticosteroids for life. And with appropriate dosing and monitoring, even these pets can have a decent quality of life if doctors are careful in their handling of these cases. Sadly, it’s too easy for doctors and owners to give up and reach for the steroids any time a pet itches. I choose long term therapy with corticosteroids for the allergic pet only if all other safer approaches have failed after a year of tying and only if other choice is euthanasia.
My intention in relating all of these facts to you is not to scare you into avoiding corticosteroids altogether, but rather to educate you. When it comes to treating allergic skin disease, there are definitely better choices than settling for long term, high dose corticosteroids therapy. For those pets that may require corticosteroids or for those owners who want to use them on a short term basis, I prefer to use a lower dose of corticosteroids when owners agree to try nutritional supplements and other more natural therapies for pets with allergies. These therapies, discussed in the next chapter, often allow us to use lower doses of the more potent corticosteroids.
A CLOSER LOOK
The side effect of sedation from antihistamine in both people and pets is related to individual susceptibility. Some patients are more likely to experience this side effect than others are. Sedation also has to do with the type of antihistamine. So called first generation antihistamines (such as hydroxyzine, diphenhydramine, and chlorpheniramine) enter the central nervous system and brain quite easy, and cause sedation. Second generation antihistamine (such as loratidine and terfenadine) do not enter the central nervous system as easily and are less likely to cause sedation. On the other hand, terfenadine has been reported to cause serious heart arrhythmias in people. This is most likely to occur in those with liver disease or low blood magnesium or potassium, and when terfenadine is used with drugs such as ketoconazole, itraconazole, and erythromycin. This is probably true for dogs a well as for humans, although use of terfenadine is uncommon in pets, and the tree drugs mentioned that negatively interact with it are likely to be used (although it’s possible).
ANTIHISTAMINES
Antihistamines are the other medications often recommended by veterinarians to decrease itching in allergic dogs. For long term use, antihistamines are preferable to corticosteroids because they have fewer side effects.
Histamine is a chemical released by mast cell and basophil cells in the pet’s body in response to contact with the allergen (foreign substance such as mold, ragweed, grass protein, etc.).
Histamine locks onto histamine receptors located on various cells throughout the body. When histamine locks onto the receptor, the cell undergoes biochemical changes and produces the clinical signs associated with allergies, such as itching and runny eyes and nose and the release of other chemicals that increase inflammation, and an accumulation of inflammatory cells.
Antihistamines work by blocking the histamine receptors. In so doing, the antihistamine, physically prevent histamine from connecting with its receptor, preventing the reactions listed above. Results are variable from 10 percent to 30 percent of dogs showing improvement.
Antihistamines are not as effective in allergic pets as corticosteroids. This is because antihistamines function by blocking the histamine receptors on cell in the body; whereas corticosteroids function by preventing the formation of prostaglandins and other chemicals that cause itching as well as by stabilizing allergy cells to prevent them from “breaking apart” and releasing their chemical mediators in inflammation. Also keep in mind that histamine is only one of many chemicals release by allergy cells (mast cells). This means that all of the other chemicals released upon contact with the allergen remain free to cause itching even though histamine may be prevented from doing so. Additionally, antihistamine work best to prevent itching before allergy signs are evident; they are not as effective in decreasing itching once the pet is severely itchy.
HYPOSENSITIZATION
FOR THOSE PETS that do not respond to other conventional therapies, hyposensitization may be necessary. Hyposensitization involves weekly injections of antigens (foreign proteins to which the dog has exhibited allergies), which are commonly referred to as allergy shots. After skin testing to determine the exact protein that affects the dog, the doctor compounds a solution containing that allergen. The idea is that the dog’s body will be sensitized to the protein and experience fewer allergic signs upon the next exposure to the allergen.
It may surprise you when I mention that antigen injections are actually a somewhat “homeopathic” approach to treating the pet with Atopic dermatitis. Many people think of allergy shots as only a conventional medicine, but think about it. Homeopathy stimulates the body to heal itself. While it doesn’t use shots to deliver its medicine, the remedies (in pill form) are diluted solutions of products that in stronger amounts would actually cause the disease. With conventional allergy shots, diluted amounts of foreign proteins (allergens) are used to get the body not to respond in an allergic way, but rather in a healing way.
That said, I try to avoid hyposensitization if at all possible. First, it is rarely necessary as most pets respond to the various complementary therapies listed in this book. Second, there are potential side effects of hyposensitization, including allergic reactions to the injected antigens. Third, antigen injections are expensive, although by no means cost prohibitive for most owners. Fourth, it takes at least 12 months to determine if the pet is responding to the injections. This means the dog requires other form of care for an entire year while you and your veterinarian wait to see if hyposensitization will work. Fifth, only about 70 percent of the dogs treated are still horribly allergic at the end of the trial year.
I only use hyposensitization under two circumstances. In the first circumstance, I’ve tried everything possible, but the dog has not improved and requires very high doses of corticosteroids to even survive with its allergic disorder. The second circumstance is when the owner wants to pursue that therapy. Some owners do not have the patience or interest in trying a number of complementary therapies for their allergic pets. In a few cases, the owners I see are fed up with frequent veterinary visits, trying one drug after another, and dealing with pets that itch and smell. Some are literally at their wit’s end! For those who no longer have the interest or patience to wait and see if complementary therapies will help their pets. I do not hesitate to refer their dog to a dermatologist for skin testing and antigen therapy. I encourage them to keep trying some of my suggested holistic approaches as hyposensitization will require 12 or more months of their patience before they know if his therapy is effective for their dog!
HOW HYPOSENSITIZATION WORKS
We’re not really sure why hyposensitzation works, but there are several theories. Perhaps it causes reduced levels of IgE. Remember that IgE antibodies bind to the allergens and mast cells and cause the pet to itch. It may be that desensitization of allergic cells reduces the reactivity of mast and other allergic cells. Then again immunization maybe the mechanism, much like vaccination in which a different class of antibodies, possibly IgE, is formed instead of IgE. Another theory is the development of tolerance as the body form allergens specific suppressor cells that suppress the allergic response. Of course, it could be a combination of any or all of these theories.
If you elect to try hyposensitization on your dog, be sure that he is properly diagnosed and that the antigen therapy is based on accurate skin testing. You also should at the very least improve you pet’s diet and begin nutritional supplement and topical decontamination. These letter ideas and other complementary therapy approaches are discussed in the next chapter.
