The thyroid glands are two separate glands found in the neck area, on either side of the trachea.  They are not usually palpable unless they are enlarged.  The primary function of the thyroid glands is to produce thyroid hormones that help help regulate the body metabolism, also known as basal metabolic rate.

If you remember in older cars, there was an instrument called a regulator.  It kept the engine from idling too fast or too slow.  This is similar to what the thyroid gland does.  When the body is revving up, the thyroid gland will slow it down.  When the body is too sluggish, the thyroid will speed it back up.  It is a homeostatis regulating gland.  When there is not enough thyroid hormone production, the body’s metabolic rate (resting energy) slows down, and when there is too much thyroid hormone production, the body’s metabolic rate speeds up.  The amount of abnormal hormone production is directly related to the symptoms that are seen with thyroid disease.

Hypothyroidism in Dogs

Hypothyroidism is a common metabolic disease found in middle-aged and senior dogs.  Symptoms associated with hypothyroidism include sluggishness, weight gain in spite of normal appetite, thickening of the skin, hair loss and seeking warmth.  Other, less common symptoms can occur such as neuropathies, megaesophagus, laryngeal paresis and others.

Hypothyroidism in dogs is usually caused by diseases of the thyroid gland such as chronic inflammation and immune-mediated diseases.  It is uncommon for cancer to cause hypothyroidism.  However, if hyperthyroidism is diagnosed (extremely rare), then there is likely an active tumor in the thyroid gland.  Conventional treatment consists of thyroid supplementation (thyroxine), usually for the rest of the dog’s life.  

“Sick thyroid syndrome” is commonly found when the vet does blood work on the dog and finds a low thyroid hormone level.  There are usually no typical symptoms of hypothyroidism.  In these cases, the thyroid gland is reacting to an underlying disease process and when the disease is resolved, the thyroid gland returns to normal function.  Often, veterinarians mistakenly diagnose these dogs as hypothyroid and place them on supplements.  If the underlying disease is corrected and the dog continues thyroid supplement, the dog will become hyperthyroid and show typical symptoms associated with over-production of the hormones.  Chronic skin disease is often a cause for sick thyroid syndrome.  

Note:  Hypothyroidism does not cause a dog to itch or scratch.  If your dog scratches consistently and has been diagnosed with hypothyroidism, there are multiple problems going on and attention should be directed at other diseases that cause itching (allergies, etc.)

Holistic Approach to Hypothyroidism

In Chinese Medicine, hypothyroidism is always a deficiency pattern.  This explains the lethargy and weight gain.  The imbalance that is usually associated with hypothyroidism in both dogs and people is kidney yang deficiency.  Some patients also show signs of phlegm-heat.  Chinese herbs that are used to re-establish balance focus on strengthening kidney yang.  They include Shen Qi Wan (Kidney qi pill), Rehmannia 8,  and Be Wei Di Huang Wan.  Beneficial acupuncture points include:  Kid3,7 and BL23.

Patients with sick thyroid syndrome are usually blood deficient which is the cause of the other diseases such as chronic skin problems.  The primary herb formula for these dogs is Jia Bing Fang.  Acupuncture points would include:  BL17, SP6,10.

Supplements that have been shown to improve thyroid function and regulation include kelp and astragalus.

Hyperthyroidism in Cats

Hyperthyroidism in cats is a very common disease that usually affects senior cats.  Unlike hypothyroidism in dogs, hyperthyroidism is an over-production of thyroid hormones, which causes an increase in basal metabolic rate.  This explains the symptoms associated with the disease.

Hyperthyroidism in cats occurs when there is a focal mass found on one or both of the thyroid glands.  These are rarely malignant and are usually considered benign tumors that are active in over-producing the thyroid hormones, T3 and T4.  The underlying cause of these tumors is not known but factors that are associated with the disease include improper utilization of Iodine.

Symptoms include rapid heart rate, often leading to heart disease, hypertension, weight loss even though the cat has a big appetite, diarrhea, abnormal night-time behavior such as howling.

Conventional western medicine treatment includes, surgical removal of the affected thyroid gland, drug therapy with anti-thyroid medications such as Methimazole and Radioactive iodine therapy.

Holistic Approach to Hyperthyroidism

From a holistic perspective, hyperthyroidism is a chronic condition caused by several imbalances.  Interference of Iodine regulation is also a part of the problem.  It has a very insidious onset and its goes for long periods of times and continuation of imbalances leading to other imbalance before the typical symptoms occur.

By the time most cats have been diagnosed with hyperthyroidism, the primary imbalance is associated with an imbalanced liver with excess liver yang (fire) that has led to yin deficiency.  The Chinese herbal formula often used is Hyper Jia Bing in earlier stages and Zhi Bai Di Huang Wan or Er Xian Tang in the later stages, particularly if the kidney function is involved.  Acupuncture points that may help include:  LIV2,3, Kid 3,6, BL18, 23, PC6, HT7, GV14,20.

Supplements that have been known to help cats with hyperthyroidism include Bugleweed, Melissa and Carnitine.

Food plays an enormous role in thyroid function.  Feeding a fresh, balanced, species-appropriate diet is always recommended.  Avoid highly processed diets and treats.