Thyroid disease has become a major pet-health concern. For the past decade or so, veterinarians across the country have reported increasing numbers of thyroid disease in many pet species, especially in cats and dogs. According to CJ Puotinen's The Encyclopedia of Natural Pet Care (Keats, 1998), many holistic veterinarians blame this increase on the frequent use of combination vaccines, commercial pet foods and cortisone drugs.
For all the problems it can cause, the thyroid gland doesn’t look like much. It’s a tiny, two-lobed, bean-shaped gland located in an animal’s neck. Belying its puny size is the thyroid’s enormous potential to either enhance or hinder the health and well-being of nearly every cell in the body.
Thyroxin, the hormone produced by the thyroid, is the body’s prime energizer: it enhances cellular reactions and increases oxygen consumption in each of the trillions of cells located in all parts of the body. Unfortunately, a pet’s thyroid is susceptible to myriad outside influences that affect its ability to function properly, and a diseased thyroid gland produces abnormal amounts of thyroxin (either too little or too much). When the thyroid has run amok, a pet can have any number of symptoms, which can vary in intensity from mild to profound.
Thyroid disease typically occurs differently in cats and dogs. In dogs, thyroid disease is usually hypothyroid (too little thyroxin); cats typically have hyperthyroidism (too much thyroxin). In either case, I treat these as imbalances of the thyroid gland, and I try to holistically support the thyroid and the other major body systems that are likely affected.
The good news is that my results using holistic medicines (herbs, acupuncture, homeopathy and nutrition) have been at least as rewarding (and generally far better) than back in the days when I was still using Western medicines.
Symptoms of Hypothyroidism
Although hypothyroidism can be seen in all animals, it’s most common in middle-aged (4- to 10-year-old) mid- to large-sized dogs.
Hypothyroidism symptoms include mental dullness, lethargy, intolerance of exercise, weight gain without a corresponding increase in appetite and intolerance to cold temperatures.
Skin and coat problems are common with hypothyroidism and include dryness, excessive shedding and retarded hair growth leading to thinning or actual loss of portions of the hair coat. Some animals also have skin swelling — especially around the face — that gives them a classic “tragic” look.
The typical hypothyroid dog has a sparse, thinning coat and dry hair and skin. Oftentimes, the skin is discolored black (often seen along the inner flank areas). Clients often complain their dog doesn’t seem to have as much energy and that he always seems cold.
Although you would expect a hypothyroid animal to gain weight (without increasing his groceries), this has not always been the case with my patients. In fact, many of my hypothyroid animals have actually been thinner than normal. Go figure.
Possible Causes of Hypothyroidism
While there is no simple, one-cause answer for the tremendous number of cases of thyroid disease we see in dogs, the way our pets live in today’s world has much to do with their thyroid problems. More than 95 percent of clinical cases of canine hypothyroidism result from the destruction of the thyroid gland itself, and most of this glandular destruction can be attributed to immune-mediated causes or other avoidable causes.
Cortisol excess (endogenous or exogenous). Corticosteroid-type drug therapy for “itchy-skin syndrome” is a common external (exogenous) source of cortisol, and persistent stress is an internal (endogenous) source.
Lack of exercise may decrease thyroxin output.
Nutritional factors. For example, the thyroid requires iodine to function but an excess can be toxic. Selenium is also a required mineral; once again, too much can be toxic. Check with your veterinarian to ensure your pet is eating a proper diet.
Toxins. Exposure to toxic chemicals, pesticides, herbicides, preservatives in foods and heavy metals (especially mercury) may compromise the thyroid, leading to the autoimmune reactions that cause disease, including thyroidal imbalance and cancers.
Genetics. A high incidence of thyroid disease often occurs along a whole bloodline of pets.
Symptoms of Hyperthyroidism
Although hyperthyroidism can occur in all animals, it’s most common in middle-aged to elderly cats. Its usual cause in cats is a thyroxin-producing thyroid adenoma (cancer). The symptoms that may be seen with an increased amount of thyroxin, as you’d expect, reflect an animal’s metabolism that has gone awry: increased appetite, weight loss, hyper-excitability and increased thirst and urination.
Many animals also have gastrointestinal upsets such as vomiting and diarrhea, and some experience an increased heart rate that, if extreme, can be life threatening. The thyroid may become enlarged enough that you can feel it in your cat’s neck.
Many of the cats I’ve seen with hyperthyroidism have the above symptoms in excess. They will eat as if they haven’t had a meal in the past four weeks, and as soon as they’re done, they’ll eat again. All this and they still lose weight. It seems that no matter how ravenous their appetite, they gradually deteriorate to skin and bones.
A hyperthyroid cat may also be a nervous wreck, pacing the floor at all hours, whining and wailing. This reaction is similar to, but is more intense and lasts longer than, what you’ll see when a female cat is in heat. Many have on-and-off bouts of diarrhea, sometimes severe. Increased heart rate with increased intensity is a common symptom in cats with hyperthyroidism.
Diagnosing Thyroid Disease
With the wide range of symptoms that may indicate thyroid disease, accurate diagnosis is sometimes difficult at best. Even the simple-to-use blood test can yield confusing results, especially when used to diagnose hypothyroidism.
The initial screening test for hypothyroidism (called the T-4 test) may provide normal results when the thyroid function is actually decreased (hypothyroid), and conversely, T-4 is often low when other diseases (unrelated to the thyroid) are really the cause of the symptoms. Another test, the TSH-stimulating test (TSH stands for thyroid stimulating hormone) adds to the accuracy of our thyroid-testing methods, but even this test is not always diagnostically definitive.
If your dog’s T-4 is low, wait a couple of months (and, if possible, clear up any ongoing diseases), then have your vet retake the T-4. If the T-4 is still low, have a TSH-stimulating test performed. In the meantime, while you’re waiting to determine if your dog’s thyroid actually is diseased, you can go ahead with herbal and nutritional therapy. If your dog’s response is good (good response to therapy is a valid diagnostic tool), there’s really no need to worry too much about test results.
One final and very important word about thyroid tests: I’ve had excellent results treating both hyper- and hypothyroidism using alternative medicines only. But, I’ve noticed that in some of the animals I’m treating — even though their symptoms have disappeared (that is, by all external appearances they’ve returned to a normally functioning critter) — their T-4 levels may remain abnormal for several months. I caution folks that we may need to wait at least several months, continuing the herbal and nutritional therapy as needed, before the blood tests return to normal.
Treating Thyroid Imbalances
Conventional hypothyroidism treatment involves using a synthetic thyroxin drug in an attempt to come up with the dosage of the drug that re-supplies the amount of the hormone a normally functioning gland should provide. The problem with this approach is that with a supply of synthetic thyroid readily available, the thyroid gland’s feedback system tells it that it does not need to produce any more hormone. So, it simply shuts down, and your pet may never again be able to develop a properly functioning gland.
Although I’ve treated some cases of severe hypothyroidism in which it has ultimately become necessary to add small amounts of synthetic thyroid supplementation, for the most part I’ve been able to re-stimulate normal thyroid function with homeopathic levels of thyroid along with herbs and other therapies. With this approach, we’re often ultimately able to return the thyroid to its normally functioning levels.
A similar problem occurs when hyperthyroidism is treated using Western medicines. Conventional therapy for hyperthyroidism consists of some method of destroying the thyroid — such as chemically or surgically. Once you’ve destroyed or surgically removed the thyroid, your only hope is to try to restore the thyroid’s normal functions with synthetic doses of hormones. In a practical sense, this isn’t always possible, so I discourage this approach unless it’s absolutely necessary.
Furthermore, as a holistic veterinarian, I think we are meowing up the wrong tree when we say cancer causes hyperthyroidism in cats. I think that some abnormal stimulus causes an imbalance in a cat’s thyroid, which then leads to abnormal growth of thyroidal cells, better known as cancer. I’m convinced outside factors are causing the tremendous increase in thyroid imbalance cases we’re seeing today. And so, I treat all cases of thyroid imbalance — both hyper- and hypothyroidism — by trying to bring the gland back into balance.
Holistic treatment of thyroid imbalance includes suitable attention to nutrition, proper exercise, removal of possible causes of toxicity (including drugs), the minimization of stress and appropriate thyroid supplementation with hypothyroidism or foods to suppress thyroid activity with hyperthyroidism. I’ve had the most success treating either disease when I’ve used constitutional homeopathy or acupuncture with my overall treatment regime — which always includes herbs.
Herbs for Hypothyroidism (Typically in Dogs)
Seaweeds. There are many types of seaweeds, and the names are often used interchangeably. These include bladderwrack (Fucus vesiculosus), kelp (Laminaria spp.), Irish moss (Chondrus crispus), nori, dulse and more. All these sea herbs contain high levels of vitamins and minerals, and they’re the highest sources of plant iodine found anywhere. They are considered specific herbs for the underachieving thyroid gland. Also, the alginate found in many of these species prevents the absorption of strontium 90, making them possible sources to counter heavy-metal poisoning.
Herbs for Hyperthyroidism (Typically in Cats)
Bugleweed (Lycopus virginicus) is a specific herb to help moderate the overactive thyroid. In addition, it’s a heart tonic, strengthening the heart as well as reducing its rate. Bugleweed is also a valuable sedative, helping to relax your cat when it’s hyper from the excess thyroxin.
Hawthorn (Crataegus spp.) and motherwort (Leonurus cardiaca). Both of these herbs are heart tonics, helping to moderate heart rate. Hawthorn is considered the best herbal cardiovascular tonic, and it’s often effective in combating the heart palpitations that can be seen with hyperthyroidism. Motherwort has similar tonic effects on the heart and is especially good for heart conditions associated with anxiety and tension.
Note that using either of these herbs may decrease the dosage of cardiac drugs needed to control heart palpitations, and extra caution should be used when cardiac beta-blockers have been prescribed. Check with your holistic veterinarian.
Other Herbs for Either Thyroid Condition
Eleuthero (Eleutherococcus senticosus) helps prevent both thyroid atrophy and hyperplasia. In addition, its adaptogenic qualities strengthen and balance all organ systems.
Licorice root (Glycyrrhiza glabra) is another herb used for its adaptogenic qualities — strengthening and balancing the whole body. Licorice root is also a specific herb for the adrenal gland, considered by some to be the master gland of the hormonal system.
Finally, I try to think in terms of which organ systems seem to be the most adversely affected. As an example, if the skin is showing severe signs, I would add skin-helper herbs such as yellow dock (Rumex crispus) or Oregon grape root (Mahonia aquifolium). Since the liver is almost always involved in any disease process, I usually include a liver-specific herb such as milk thistle (Silybum marianum) or dandelion root (Taraxacum officinale).
The Bottom Line
If the results I’ve seen with my patients are any indication, using herbs and other alternative methods should be your first (and possibly last) course of action when treating thyroid diseases. I’m suspicious of thyroid disease whenever I’m treating a pet with a bunch of symptoms that don’t seem to add up to any one specific disease. At the same time, I do not rely strictly on the “science” of blood chemistry test results for diagnosis. Knowing what I do today, I would always try alternative methods before I attempt Western medicine’s conventional (and confrontational) methods. And while I was helping a pet’s thyroid re-create its own balance, I wouldn’t be too disturbed if the blood chemistry results didn’t return to “normal,” as long as the pet’s general symptoms were improving.
Randy Kidd holds doctorates in veterinary medicine and veterinary and clinical pathology. After practicing traditional veterinary medicine for 10 years, he opened Honoring the Animals, a holistic practice in Kansas City, Missouri.
Information provided in “Pet Corner” is not intended to replace the advice of a qualified veterinarian.