Understanding Thyroid Disorders in Pets: A Guide for Cupertino Pet Owners

What Are Thyroid Disorders?

The thyroid gland may be small, but it plays a crucial role in regulating your pet’s metabolism and overall health. In both humans and animals, the thyroid gland secretes hormones that influence nearly every body system.

Thyroid disorders in pets primarily fall into two categories:

  • Hypothyroidism – The thyroid does not produce enough hormones, slowing metabolism (most common in dogs).
  • Hyperthyroidism – The thyroid produces excessive hormones, accelerating metabolism (most common in cats).

Early detection and management of thyroid conditions can significantly improve your pet’s health and longevity.

The Medical Perspective: How Thyroid Hormones Affect Your Pet

The thyroid hormones, thyroxine (T4) and triiodothyronine (T3), are responsible for:

  • Regulating metabolism
  • Controlling body temperature
  • Supporting heart and brain function
  • Influencing skin and coat health

An imbalance in these hormones can lead to widespread health issues, affecting cardiovascular function, behavior, and energy levels.

Identifying Hypothyroidism in Dogs: Symptoms and Diagnosis

Hypothyroidism is most common in middle-aged to older dogs and occurs when the thyroid produces insufficient hormones.

Common Symptoms of Hypothyroidism

  • Lethargy or low energy
  • Unexplained weight gain despite normal eating habits
  • Thinning coat or hair loss
  • Increased sensitivity to cold
  • Recurring skin infections or dry, flaky skin

Long-Term Effects of Untreated Hypothyroidism

If left untreated, hypothyroidism can lead to:

  • Heart disease
  • Nerve dysfunction (weakness or poor coordination)
  • Obesity-related complications
  • Infertility in breeding dogs

How Hypothyroidism is Diagnosed

Veterinarians use blood tests to measure thyroid hormone levels, including:

  • Total T4 (thyroxine) – The primary screening test.
  • Free T4 and TSH (thyroid-stimulating hormone) – Used for a more accurate diagnosis.

Learn more about hypothyroidism in dogs from Cornell Vet.

Understanding Hyperthyroidism in Cats: Symptoms and Diagnosis

Hyperthyroidism is most common in cats over 10 years old and results from an overactive thyroid producing excess hormones.

Common Symptoms of Hyperthyroidism

  • Significant weight loss despite an increased appetite
  • Hyperactivity and restlessness
  • Increased vocalization (yowling or meowing more than usual)
  • Vomiting or diarrhea
  • Unkempt, greasy, or patchy fur

The Dangers of Untreated Hyperthyroidism

Without treatment, hyperthyroidism can cause:

  • High blood pressure (hypertension)
  • Heart disease
  • Kidney damage
  • Increased risk of sudden heart failure

How Hyperthyroidism is Diagnosed

Veterinarians confirm hyperthyroidism with:

  • Blood tests measuring T4 levels
  • Additional imaging (thyroid scintigraphy) in complex cases

Learn more about feline hyperthyroidism from Cornell Feline Health Center.

Treatment Options for Thyroid Disorders in Pets

Treatment for Hypothyroidism in Dogs

The standard treatment for hypothyroidism in dogs is daily thyroid hormone replacement therapy using levothyroxine.

Regular monitoring is essential to ensure correct dosing. Blood tests are conducted periodically to assess hormone levels and adjust medication if needed.

Treatment for Hyperthyroidism in Cats

There are multiple treatment options for hyperthyroid cats, including:

  • Medications (Methimazole) – Controls hormone production but requires daily administration.
  • Radioactive iodine therapy (I-131) – A curative option that destroys overactive thyroid tissue.
  • Surgery (thyroidectomy) – Removes the affected thyroid gland but is less common due to surgical risks.
  • Prescription diets (low iodine food) – Can help manage hormone production in certain cases.

Your veterinarian will determine the best treatment based on your cat’s overall health, age, and condition severity.

Managing Your Pet’s Thyroid Health: Diet and Lifestyle Adjustments

Nutritional Support for Thyroid Conditions

  • Hypothyroid dogs benefit from a well-balanced diet with high-quality protein and omega fatty acids to support coat health.
  • Hyperthyroid cats may require a low-iodine diet to help regulate thyroid hormone levels.

Home Care and Prevention

  • Regular Check-Ups: Routine vet visits help monitor thyroid function and adjust treatment plans.
  • Watch for Symptoms: Keep track of weight, energy levels, and changes in appetite or coat quality.
  • Provide Consistent Medication: Stick to prescribed dosages and follow up on scheduled blood tests.

Frequently Asked Questions About Pet Thyroid Health

Can thyroid disorders be cured?

  • Hypothyroidism in dogs is managed, not cured, with lifelong medication.
  • Hyperthyroidism in cats can be cured with radioactive iodine therapy or surgery in some cases.

What happens if thyroid disease is left untreated?

  • Untreated hypothyroidism can lead to obesity, heart disease, and reduced quality of life.
  • Untreated hyperthyroidism can cause severe heart and kidney damage and shorten lifespan.

Are thyroid problems hereditary?

Yes, some breeds have a genetic predisposition. Golden Retrievers, Dobermans, and Irish Setters are more prone to hypothyroidism.

What does a thyroid emergency look like?

Signs of a thyroid crisis may include:

  • Sudden lethargy or collapse
  • Severe weight loss or dehydration
  • Uncontrolled heart rate or breathing difficulties

Seek immediate veterinary attention if your pet shows these signs.

How Cupertino Animal Hospital Can Help Your Pet With Thyroid Disorders

At Cupertino Animal Hospital, we specialize in diagnosing and treating thyroid disorders in dogs and cats. Our team uses advanced diagnostics and personalized treatment plans to ensure your pet receives the best care possible.

We provide:

  • Comprehensive thyroid screenings
  • Tailored treatment plans for hypothyroid and hyperthyroid pets
  • Ongoing monitoring and support

Schedule a Thyroid Health Consultation Today

If your pet is showing any symptoms of thyroid disease, don’t wait—early diagnosis leads to better outcomes.

Request an appointment at Cupertino Animal Hospital today to discuss your pet’s thyroid health and ensure they receive the care they need.