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Diet For Cats With Hyperthyroidism

Your cat's thyroid gland produces hormones that regulate numerous bodily processes. When thyroid hormone levels rise excessively (hyperthyroidism), your cat faces the risk of developing severe health complications. Today, our veterinarians in Mount Vernon discuss how dietary changes can treat cat hyperthyroidism.

What is hyperthyroidism in cats?

The thyroid glands in your cat's neck actively produce various hormones crucial for regulating numerous body processes and controlling your cat's metabolic rate.

When the thyroid produces excessive or insufficient amounts of these hormones, your cat will exhibit symptoms of either hypothyroidism (low hormone levels) or hyperthyroidism (excessive hormone levels).

In the case of hyperthyroidism, your cat's metabolism accelerates. Consequently, your cat will burn energy at an accelerated rate, leading to weight loss despite an increased food intake.

What are the symptoms of hyperthyroidism in cats?

While any breed of cat can suffer from hyperthyroidism, most cats diagnosed with this condition are older. Typically between 12 and 13 years old. Female and male cats are equally impacted.

The symptoms of hyperthyroidism in cats often start subtly in the early days but progressively worsen over time. Additionally, other underlying health issues can complicate or conceal hyperthyroidism symptoms.

Therefore, it's crucial to promptly consult your vet if your cat exhibits any of the following symptoms. Cats with excessive thyroid hormone production may display 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 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?

Left untreated, hyperthyroidism can impact your cat's heart function and potentially lead to heart failure.

Your cat may also develop high blood pressure due to hyperthyroidism. Although less common, high blood pressure in cats is associated with other serious health issues such as brain, kidney, heart, and eye damage. If your kitty is diagnosed with hypertension alongside hyperthyroidism, medication will be necessary to control their blood pressure.

Hyperthyroidism and kidney disease often coexist in older cats. When both conditions are present, they require close monitoring and management because treating hyperthyroidism can sometimes negatively affect kidney function.

How is hyperthyroidism diagnosed?

Diagnosing hyperthyroidism in older cats requires precision. Your vet will conduct a physical exam and palpate your cat's neck area to detect signs of an enlarged thyroid gland. At Northwest Veterinary Clinic of Mount Vernon, our veterinary internal medicine team employs diagnostic testing to diagnose your pet's condition and offer advanced care accurately.

Since various conditions exhibit similar symptoms to hyperthyroidism, we utilize a range of tests to diagnose your cat's condition. Conducting a complete blood count (CBC), urinalysis, and chemistry panel aids in ruling out kidney failure and diabetes. Elevated T4 levels in the bloodstream, revealed through a simple blood test, can often confirm the diagnosis definitively. Your vet may also assess your kitty's blood pressure or conduct additional tests such as an electrocardiogram, chest 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?

Your vet can often manage hyperthyroidism in cats by prescribing an iodine-restricted diet. Thyroid hormones require iodine for production, so this therapeutic diet aims to curb hormone production by limiting iodine intake in your cat's food.

To ensure the effectiveness of this treatment, strict adherence to the low-iodine diet is crucial. However, sticking to it can be challenging for some pet parents and their cats. Besides providing your cat with prescription food, you must closely monitor their treats and prevent them from hunting for food outside.

Studies indicate that thyroid hormone levels typically start to decline after three weeks of following the prescribed hyperthyroidism diet. With continued adherence, hormone levels may even normalize within a few months.

What is the prognosis for cats with hyperthyroidism?

If the condition is diagnosed and treated early, the prognosis for cats suffering from hyperthyroidism is generally good. In some cases where the condition has become more advanced, complications with other organs can 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 Mount Vernon vets today to book an appointment for your feline friend.

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Northwest Veterinary Clinic of Mount Vernon is accepting new patients! Our vets are passionate about the health of Mount Vernon cats, dogs, and horses. Get in touch today to book your animal's first appointment.

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