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Diet For Cats With Hyperthyroidism

Your cat's thyroid gland produces hormones that are responsible for regulating various processes within the body. However, when the thyroid hormone levels become too high, a condition called hyperthyroidism can develop, which poses a serious health risk for your cat. Our vets in Clearlake share some valuable insights on how hyperthyroidism in cats can be managed through dietary changes.

What is hyperthyroidism in cats?

The thyroid glands are located in your cat's neck and produce various hormones that regulate many processes in the body and control your cat's metabolic rate. If the thyroid produces too much or too little of these hormones, your cat will either show symptoms of hypothyroidism (low levels of hormone) or hyperthyroidism (too much hormone).

If your cat is suffering from hyperthyroidism, their metabolism will speed up, causing your cat to burn energy too quickly. This will result in weight loss, even if you notice that your kitty is eating considerably more food than usual.

What are the symptoms of hyperthyroidism in cats?

Although all breeds of cats can suffer from hyperthyroidism, most cats diagnosed with this disease are older. They are generally between 12 and 13 years of age. Male and female cats are equally affected.

Symptoms of hyperthyroidism in cats are often subtle in the early days but progressively worsen over time. Other underlying health problems can also complicate or mask the symptoms of hyperthyroidism.

So it's important to consult your vet promptly if your cat displays any of the symptoms listed below. Cats producing too much thyroid hormone may present one or more of the following symptoms:

  • Increase in thirst
  • Irritability
  • Restlessness
  • Mild diarrhea and vomiting
  • Increase in heart rate
  • Poor grooming habits
  • Hearty or increased appetite
  • Low heat tolerance 

When the condition becomes more advanced, some cats will pant when they are stressed which is unusual for cats. Although most cats suffering from hyperthyroidism have a good appetite and are restless, others may feel weak, lethargic or experience a lack of appetite. 

What causes hyperthyroidism?

Hyperthyroidism is most often caused by a non-cancerous tumor located somewhere on the thyroid gland. In some rare cases, however, the tumor can develop into thyroid cancer.

What are the long-term complications of hyperthyroidism?

If left untreated, hyperthyroidism can affect the function of your cat's heart, which can lead to heart failure.

Additionally, hyperthyroidism in cats can cause high blood pressure, which can result in serious health concerns such as damage to the brain, kidneys, heart, and eyes.

If your feline friend is diagnosed with hypertension in addition to hyperthyroidism, medication will be required to control their blood pressure.

It's worth noting that hyperthyroidism and kidney disease often occur simultaneously in older cats. When both conditions are present, they need to be closely monitored and managed as treating hyperthyroidism can sometimes have an adverse effect on kidney function.

How is hyperthyroidism diagnosed?

Diagnosing hyperthyroidism in older cats can be somewhat tricky. Your vet will complete a physical exam and palpate your cat’s neck area to look for signs of an enlarged thyroid gland. At Clearlake Veterinary Clinic our veterinary internal medicine team uses in-house diagnostic testing to help diagnose your pet's condition and provide advanced care.

As the clinical symptoms of hyperthyroidism are common to a wide range of conditions, a variety of tests can be used to diagnose your cat's condition. A complete blood count (CBC), urinalysis, and chemistry panel can help rule out renal failure and diabetes. A simple blood test showing elevated levels of T4 in the bloodstream may be enough to make a definitive diagnosis. Your vet may also check your kitten's blood pressure or perform an electrocardiogram, lung x-ray, or ultrasound.

How will my vet treat my cat’s hyperthyroidism?

Depending on the results of your cat's tests, your vet may choose one of several treatment options for your cat’s hyperthyroidism.  They may include:

  • Radioactive iodine therapy (likely the safest and most effective treatment option)
  • Antithyroid medication
  • Surgery to remove the thyroid
  • Modified diet

How can hyperthyroidism be treated with a modified diet?

Hyperthyroidism is a common condition in cats, but it can be managed through an iodine-restricted prescription diet recommended by your veterinarian. Iodine is essential for the production of thyroid hormones, and the purpose of an iodine-restricted therapeutic diet is to reduce the production of these hormones by limiting the iodine in your cat's diet.

It is crucial to strictly adhere to the low-iodine diet to make this treatment effective, which can be challenging for both pet parents and their cats. In addition to feeding your cat a prescription food, you must also monitor your cat's treats closely and prevent them from hunting for their food while outside.

According to some studies, after following a prescription hyperthyroidism diet for three weeks, the levels of thyroid hormones begin to decrease, and within a few months, they may even return to normal levels.

What is the prognosis for cats with hyperthyroidism?

If caught and treated early, cats with hyperthyroidism have a good chance of recovery. However, in severe cases, other organs can be affected and worsen the prognosis.

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.

If your cat is suffering from hyperthyroidism? Our vets can help! Contact our Clearlake vets today to book an appointment for your feline friend.

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