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Hyperthyroidism in Cats: Symptoms

When a cat's thyroid glands do not function properly, it can impact critical systems in the body. Here, our Springfield vet specialists discuss overactive thyroid glands, the symptoms that may be experienced, and what diet may benefit cats with hyperthyroidism.

Hyperthyroidism in Cats

Hyperthyroidism in cats happens when their thyroid gland begins to overproduce hormones, usually once they are well into their senior years. Unfortunately, when the thyroid gland creates more of the hormone than is needed, it can begin to harm your feline friend's heart and other organs.

One of the most common causes of hyperthyroidism in cats is non-cancerous tumors, while these can occasionally turn out to be cancer.

If your cat shows any signs of hyperthyroidism, you should contact your vet to have it examined immediately. Your cat will have a better chance of living comfortably when diagnosed and treated early.

Common Signs & Symptoms of Hyperthyroidism

With hyperthyroidism in cats, the typical symptoms may include:

  • Weight Loss
  • Increased Thirst
  • Increased Urination
  • Vomiting / Diarrhea
  • Restlessness / Hyperactivity
  • Aggressive Behavior
  • Difficulty Breathing
  • Weakness
  • Depression
  • Greasy / Matted Hair

Treating Hyperthyroidism in Cats

There are several different options for hyperthyroidism in cats treatment, including:

Medication for hyperthyroidism in cats: For this treatment, you must give your cat an anti-thyroid medication that decreases thyroid hormone production twice daily for the remainder of its life.

Radioactive iodine therapy: To treat hyperthyroidism in cats, iodine therapy involves injecting iodine directly into their bodies so that it enters the bloodstream. This radioactive iodine will then travel through the body, destroying any abnormal cells it comes into contact with. You can expect results in as little as a few weeks.

Surgical treatment for hyperthyroidism in cats: One of the potential options for treating hyperthyroidism in cats is surgical intervention. Your vet would surgically remove the thyroid, which eliminates the need for daily medications. Your vet must complete diagnostics before surgery to ensure your cat can safely undergo anesthesia.

Treating Hyperthyroidism with dietary changes: Your vet may also suggest changing your cat's diet to alter the amount of iodine, which might affect its thyroid. This treatment is still a relatively new option; you should consult your vet before making any changes.

Hyperthyroidism in Cats: Diet

Cats with hyperthyroidism, especially older felines whose bodies may find it challenging to absorb essential nutrients, can lose significant weight. So, what cat food is best for hyperthyroidism? Generally, cats with overactive thyroid glands require a high-calorie diet with enough fat and plenty of high-quality, animal-based protein.

Your vet can recommend cat food and diet to help manage hyperthyroidism. With hyperthyroidism, many vets recommend an iodine-restricted diet for cats. This iodine-restricted diet aims to decrease the production of thyroid hormones in your cat's body, as thyroid hormones require iodine for their production.

Adhering strictly to the low-iodine diet is crucial to ensuring the effectiveness of this treatment. This can be challenging for some pet parents and their cats. In addition to feeding your cat the prescription food, you must closely monitor your cat's treats and prevent them from hunting for mice or birds outdoors.

Your cat may not enjoy their low-iodine diet, and the uncomfortable symptoms of hyperthyroidism will probably continue if you try to mix a low-iodine food plan with your cat's regular food. However, it's important to stick to the diet plan prescribed by your vet.

Your vet may recommend avoiding products such as supplements, human food, and some flavored medications to help lower your cat's consumption of iodine. Studies indicate that following a prescription hyperthyroidism diet for three weeks can decrease thyroid hormone levels. Within a few months, these levels may even return to normal.

Prognosis for Hyperthyroidism in Cats

Thankfully, the prognosis for cats with hyperthyroidism is quite good, especially if their condition has been diagnosed early. Regardless of the type of treatment your vet recommends, you can expect your cat to bounce back and live a happy and healthy life if you continue bringing them in for regular checkups and managing their condition.

Is hyperthyroidism in cats painful?

Without proper treatment, cats are likely to experience pain and a lower quality of life due to the symptoms related to hyperthyroidism, along with additional complications, as mentioned below.

What happens when hyperthyroidism goes untreated?

As with most conditions, leaving hyperthyroidism untreated can lead to serious complications. Your cat will become more ill over time. You may notice symptoms such as blood in their stool, and they may not eat very much, which can lead to other issues.

Many cats that are suffering from untreated hyperthyroidism experience potentially fatal heart issues due to their heart working extra hard to keep your cat's body running.

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 showing the signs listed above or has been diagnosed with hyperthyroidism, please request a referral from your primary care vet to our vet specialists in Springfield for treatment.

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The Regional Veterinary Referral Center is accepting new patients in emergency situations or by referral! Our experienced specialists are passionate about the health of Springfield pets. Contact us today to learn more.

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