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Health2026-03-107 min

Hyperthyroidism in Cats - Symptoms, Diagnosis & Treatment Options

Explore treatment options for feline hyperthyroidism including medications and radioactive iodine.

What is Feline Hyperthyroidism?

Feline hyperthyroidism occurs when the thyroid overproduces hormone. Common in older cats (8-10+ years). Proper treatment extends lifespan.

Hyperthyroidism

Hyperthyroidism

Symptoms

  • Weight loss despite increased appetite
  • Hyperactivity, anxiety
  • Rapid heart rate (heart murmur)
  • Frequent urination, increased thirst

Diagnosis

Blood tests measure T4 levels. Ultrasound checks thyroid size.

Treatment Options

  • Medication (methimazole): Lifelong treatment
  • Radioactive iodine: Possible cure (expensive)
  • Surgery (thyroidectomy): Alternative option
  • Special diet (iodine-restricted food)

Medication Management

Methimazole has side effects (low blood counts, liver damage). Regular blood tests are essential.

Sources & References

  • Cornell Feline Health Center - Hyperthyroidism

Early diagnosis and treatment greatly improve quality of life.

⚠️ Disclaimer: This article is provided for educational purposes and does not replace professional veterinary advice. Always consult with your veterinarian regarding your cat's nutrition and health.