Thyroid Disorders in Pets

The thyroid gland, located in the neck of your pet, is one of the most important hormonal glands in the body system—both for our furry friends and humans! It is responsible for regulating metabolism, growth & development, and overall health. Sometimes, however, our thyroid glands can become unbalanced, resulting in underactive or overactive production of thyroid hormone. These disorders can have a large range of symptoms and generally require medical intervention in order to properly manage them and ensure a good quality of life for your pet. Today, we will explore the causes, symptoms, and treatment options for this commonly misunderstood condition.

What are common thyroid disorders in pets and how are they caused?

1. Hypothyroidism: This refers to an underactive thyroid gland in which your pet is not producing enough thyroid hormone to satisfy their health needs. The most common cause of hypothyroidism is an autoimmune disorder called lymphocytic thyroiditis or Hashimoto's thyroiditis. If your pet has this, their immune system will mistakenly attack their thyroid gland, leaving it in a constant state of panic. Since the thyroid gland is busy protecting itself from the attack, it is not able to produce as much thyroid hormone as it normally would. This autoimmune disorder is largely genetic and is more common in some breeds than others. However, sometimes hypothyroidism and autoimmunity can also be caused by other underlying health issues or medications, such as pituitary dysfunction, congenital abnormalities, and surgical treatments that remove the thyroid gland entirely.

   
   

2. Hyperthyroidism: This refers to an overactive thyroid gland in which your pet is producing too much thyroid hormone, disrupting the natural balance in their bodies. This condition is most common in cats and is generally caused by benign tumors on their thyroid gland called adenomas. These tumors overstimulate the thyroid gland and cause an excess production of thyroid hormone. The specific cause of the development of these tumors is still being studied. However, genetic and environmental factors are likely at play. While adenomas are the most common cause of hyperthyroidism in pets, other underlying health issues, such as adenocarcinoma (malignant tumors that cause thyroid cancer), thyroiditis (inflammation of the thyroid gland), and too much iodine can also result in hyperthyroidism.

   
   

Symptoms

Common symptoms of hypothyroidism include:

1. Weight Gain: Pets with hypothyroidism often find it difficult to lose weight since the thyroid hormone is essential in managing metabolism. When there is an underproduction of thyroid hormone, it becomes a lot harder for your pets to metabolize their food, leading to weight gain even if they are on a healthy diet.

2. Fatigue: Hypothyroidism leads to a decline in all metabolic activity, including proper energy production. Thus, your pets will likely tire more easily and appear more lethargic if they have this health condition.

3. Depression: Thyroid hormones are essential in regulating a large number of neurotransmitters, including dopamine and serotonin, which are associated with mood regulation. When there is not a sufficient amount of thyroid hormone, the normal function of these neurotransmitters is disrupted, which can cause depressive behavior.

4. Dull Fur: Thyroid hormones play a key role in managing your pet's hair growth cycle. A lack of this hormone disrupts this cycle and can cause abnormal shedding and poor hair regrowth. This will cause your pet's fur to appear thinner and duller.

   
   

Common symptoms of hyperthyroidism include:

1. Weight Loss: While weight gain is associated with hypothyroidism, the opposite is true of hyperthyroidism. An excess amount of thyroid hormone can increase metabolic rates, and thus cause your pet to process calories, fat, and other nutrients much faster. While this might sound like a good thing, a healthy lifestyle is all about balance, and overactive metabolic systems can be very problematic.

2. Excessive Thirst and Urination: An increased metabolic rate leads to higher body temperatures and heat production. This can cause your pet to become dehydrated more easily, and thus need to urinate more frequently.

3. Anxiety & Hyperactivity: Thyroid hormones have a direct impact on the sympathetic nervous system, which is what is responsible for your pet's fight or flight response. When there is too much thyroid hormone, the sympathetic nervous system is overstimulated and can lead to anxious behavior and restlessness.

4. Dull Fur: Just like in hypothyroidism, a disruption in your pet's hair growth cycle can make your pet's fur appear thinner and duller.

Treatment

Generally, if your pet has hypothyroidism, they may need to be put on medication to increase their thyroid hormone levels. This will help out their overworked thyroid gland and ensure your pet has enough thyroid hormone to assist their bodies in functioning properly. Other natural remedies for hypothyroidism include herbal supplements like Ashwagandha, Siberian Ginseng, and Bladderwrack that have been known to support thyroid function. In addition, nutritious diets and regular exercise are always important.

For hyperthyroidism, the treatment largely depends on how severe your pet's case is. If it is caused by malignant tumors in the thyroid gland, generally, surgical removal or radiation therapy is recommended so the cancerous cells do not spread. However, if the tumor is benign or the condition is caused by thyroiditis, there are medications your veterinarian can prescribe. In addition, you can consider herbal treatments such as Bugleweed and Lemon Balm—both of which are known to have mild anti-thyroid effects. Of course, consult with your veterinarian before providing your pets with any herbal treatments.

Getting your pet diagnosed with a thyroid disorder can be difficult since it is often overlooked. This generally occurs since the symptoms tend to be very vague and overlap with many other health conditions. In addition, veterinarians usually do not specifically test for thyroid hormone levels during routine examinations. If you are at all worried your pet might have a thyroid condition, do not hesitate to let your veterinarian know so you can get appropriate testing and treatment done!