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Hypothyroidism in Dogs - Causes, Symptoms & Diet

Hypothyroidism in Dogs - Causes, Symptoms & Diet

Hypothyroidism is a prevalent condition in dogs that can cause unexplained weight gain, skin and coat issues, as well as behavioral changes and reduced energy. In today's article, our Portland vets explain more about this condition including the best diet for dogs with hypothyroidism.

What is hypothyroidism in dogs?

Hypothyroidism happens when your dog's thyroid gland doesn't make enough important hormones to control their metabolism, leading to a slower metabolism.

What causes hypothyroidism in dogs?

The majority of hypothyroidism cases in dogs are caused by two main conditions: lymphocytic thyroiditis and idiopathic atrophy of the thyroid gland. While these conditions are not well understood, they both result in damage to the dog's thyroid. Lymphocytic thyroiditis occurs when the dog's immune system attacks the thyroid, while idiopathic thyroid gland atrophy happens when fat replaces the thyroid tissue.

There are several claims suggesting that hypothyroidism in dogs may be caused by external factors such as a raw food diet, standard commercial dog food diet, vaccines, lawn chemicals, choke collars, environmental toxins, phthalates in dog chew toys, PCBs, and antibacterial agents in soaps. The basis for these claims is the belief that each of these factors can affect the thyroid and endocrine system in various ways. However, it is important to note that further studies are needed to draw any definitive conclusions.

What are the signs of hypothyroidism in dogs?

Hypothyroidism slows down your pet's metabolism, affecting almost every organ in their body. If your dog has hypothyroidism, you may notice the following symptoms:

  • Unexplained weight gain
  • Obesity
  • Lack of energy, lethargy
  • Mental dullness
  • Cold intolerance
  • Thinning coat
  • Dull looking fur
  • Dark pigmentation of the skin
  • Recurring ear infections
  • Recurring skin infections
  • High cholesterol
  • Slow heart rate
  • Lameness
  • Lack of coordination
  • Thickening of skin
  • Reproductive issues

If your dog shows any of these symptoms, they may be experiencing hypothyroidism. It's important to contact your vet and schedule an appointment for your dog.

When your vet suspects hypothyroidism, they will conduct a thorough physical examination and run a series of blood tests to check your dog's levels of thyroid hormones T4 and T3. Since there are other conditions with similar symptoms, the diagnostic testing may be extensive in order to confirm a definitive diagnosis.

How is hypothyroidism in dogs treated?

If your dog is diagnosed with hypothyroidism, the treatment will probably involve giving them a prescription for a synthetic thyroid hormone called levothyroxine (L-T4). It's worth mentioning that it might take a while for your pet's hormone levels to reach the optimal level, and your dog may need regular blood tests to track their progress during the treatment. Once the hormone levels stabilize, your dog will need to continue taking this prescription for the rest of their life. 

What diet should my dog with hypothyroidism eat?

For dogs with hypothyroidism, a combination of a healthy diet and hormone replacement medication can help your dog feel better. Your vet will provide instructions for the best food to feed your dog with hypothyroidism. If you want more detailed dietary guidelines, ask your vet to recommend a pet nutritionist or holistic vet near you.

Dogs with hypothyroidism need a balanced diet that includes amino acids, iodine, vitamins, minerals, probiotics, antioxidants, proteins, fats, and carbohydrates. Your vet will recommend the best diet for your dog's specific needs.

In some cases, homemade food may be recommended. If that's the case for your dog, the vet will give you recipes that provide all the necessary nutrition in the right balance.

Your vet may suggest a prescription therapeutic dog food as part of your dog's hypothyroid treatment. These diets are specially formulated to meet your pet's nutritional needs but with lower fat content.

Certain fresh vegetables, like asparagus, green beans, beets, broccoli, brussels sprouts, carrots, celery, lettuce, mushrooms, and spinach, may support thyroid function. You can include them in your dog's diet in small amounts, but always check with your vet before adding new foods.

Are there any foods to avoid when a dog has hypothyroidism?

Vets have different opinions on what to feed dogs with hypothyroidism. Some say to avoid commercial dry foods, while others suggest avoiding a raw food diet. It's always wise to consult a trained veterinary professional when it comes to feeding your dog. 

Note: The advice provided in this post is intended for informational purposes and does not constitute medical advice regarding pets. For an accurate diagnosis of your pet's condition, please make an appointment with your vet.

Is your dog showing signs of hypothyroidism and requires advanced care? Ask your vet to refer your furry friend to our Board-Certified Veterinary Internal Medicine Specialist. Get in touch with us for further details. 

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