Hyperthyroidism is one of the most common conditions we see in older cats. It happens when your cat’s thyroid glands, which are responsible for regulating metabolism, produce too much thyroid hormone. This speeds everything up-your cat’s metabolism, heart rate, and even water consumption. The good news is, it’s treatable, and we are here to help guide you through the process.
What Exactly Is Hyperthyroidism?
Your cat has two thyroid glands located in the neck. These glands are crucial for regulating your cat’s metabolic rate. Hyperthyroidism is when these glands go into overdrive and produce too much thyroid hormone, which ramps up the metabolism. While it may sound alarming, it’s typically a benign condition. Only a very small percentage of cats have a cancerous form of hyperthyroidism. This condition is most common in older cats, especially those around 12 years of age or older. As your cat ages, keeping an eye on their health becomes more important, and there’s where regular check -ups can make a big difference.
Who’s at Risk?
All cats, especially as they get older, can develop hyperthyroidism. While no breed is particularly at risk, studies show that Burmese, Persian, Siamese, Tonkinese, Abyssinian and British Shorthairs tend to have a lower chance of developing this condition.
What Causes Hyperthyroidism?
Though the exact cause of hyperthyroidism in cats is still unknown, several factors may contribute. Environmental pollutants like flame retardants and certain chemicals have been studied for their potential role in increasing risk. Additionally, diets high in iodine may increase the chances of developing this condition in susceptible cats.
Common Signs to Watch For
The most common sign of hyperthyroidism is weight loss, despite an increase in appetite. Other symptoms include restlessness, irritability, increased drinking and urination, vomiting, diarrhea, changes in vocalization (often more meowing, especially at night), and an unkempt coat. As the disease progresses, cats can also develop complications like high blood pressure and heart issues. That’s why it’s important to get a diagnosis early on.
How We Diagnose It
Diagnosing hyperthyroidism typically involves testing the levels of thyroid hormones in the blood, particularly total thyroxine (TT4). If hormone levels are elevated, the diagnosis is clear. In cases where TT4 levels are borderline, additional testing may be required to confirm the condition.
Treatment Options
We’re happy to say that hyperthyroidism is treatable! Here are the options we’ll discuss with you, depending on your cat’s specific needs:
• Medication: Methimazole is a commonly used drug to control thyroid hormone production. It is a lifelong treatment option that requires regular check-ups to monitor your cat’s progress.
• Radioactive Iodine Therapy: This is a highly effective treatment that targets and destroys the abnormal thyroid tissue. It typically requires hospitalization for a brief period (up to a week) at a specialty referral center, but offers a permanent cure in most cases.
• Surgery: Surgical removal of the thyroid gland is another option for cats that are healthy enough to undergo anesthesia. This treatment may be recommended if medication is not well-tolerated or if radioactive iodine is not available.
• Special Diet: Prescription diets that limit iodine intake can help manage hyperthyroidism by reducing the thyroid’s ability to produce excessive hormones. However, these diets must be strictly followed for the treatment to be effective.
Managing Complications
Because hyperthyroidism can put stress on your cat’s heart and kidneys, we’ll keep an eye on these organs too. If your cat has high blood pressure or heart disease, we’ll work on treating those complications alongside the thyroid condition.
Can Hyperthyroidism Be Prevented?
There is no known way to prevent hyperthyroidism, but regular check-ups and blood tests can catch it early before it causes serious issues. That’s why we recommend bringing in your senior cat for a thorough exam at least twice a year. Early detection can make a world of difference in keeping your cat healthy and happy.
My Own Experience
I know firsthand how important it is to catch and treat hyperthyroidism early. My own cat, Bella, was diagnosed with hyperthyroidism, and he is now being treated with methimazole and doing very well. It’s been reassuring to see his respond to the treatment, and I want to make sure your cat has the same opportunity to stay healthy and happy.
We are Here to Help
If you’ve noticed changes in your cat’s weight, appetite, or behavior, or if you just want to ensure they’re staying healthy as they age, don’t hesitate to reach out to us at Valley Veterinary Services. We’re here to help you and your furry friend every step of the way!
Written by Dr. Yuri Yoon