What You Should Know About Hyperthyroidism in Cats

Bootsy The Cat has been there for you through thick and thin. He may be getting a little older, but at 14 he hasn’t been sick a day in his life. He seems to be doing great and he is eating well, but over the past few months you have noticed his hips and spine sticking out a little more than they used to. It’s normal for old cats to lose a little weight, though, right?

You decide that maybe it’s best to get Bootsy checked out and bring him in for a checkup. When we place him on the scale to weigh in, you are astonished to see that he has lost almost a pound since his last visit less than a year ago. What could be going on?

As you may realize, it’s not always obvious that your cat is sick. There are many conditions that could be plaguing Bootsy; however, at the top of our list of suspects, is hyperthyroidism.

Hyperthyroidism in cats is an all too common problem that all cat owners should be familiar with so that they can help recognize the signs early.

Understanding Hyperthyroidism in Cats

The thyroid gland is an important organ in all of our bodies. This little gland that lives in the neck region secretes a hormone that helps to regulate the body’s metabolism. The amount of this hormone in circulation is essential to keeping things in balance.

For reasons we don’t thoroughly understand, it is not uncommon for cats to begin to secrete too much thyroid hormone. Many times this is associated with a harmless but functional tumor in the thyroid gland itself. When too much thyroid hormone enters circulation, the metabolism increases, resulting in a few characteristic symptoms. These include:

• Weight loss despite a good (often ravenous) appetite
• Increased heart rate
• High blood pressure and other cardiac complications
• Vomiting or diarrhea in some cats
• Changes in vision due to blood pressure issues

Untreated, hyperthyroidism in cats have serious consequences.

What We Can Do

If we suspect that a cat may be suffering from hyperthyroidism, diagnostic tests such as blood and urine testing are needed to rule out other possible causes of the symptoms and confirm the diagnosis.  

Thankfully, hyperthyroidism is a very manageable condition in most cats. We have a few very effective options for keeping the symptoms under control and preventing the dangerous side effects of the disease. Depending on the situation, a hyperthyroid cat may be treated with:

• Oral medication – Most cats can be successfully managed on oral medications to lower thyroid hormone. These must be administered daily (usually morning and night) for life. This type of medication is most readily available as a tablet, however liquid and transdermal formulations are often used due to the ease of administration.
• Prescription diet – For some cats, eating a prescription diet designed to decrease the production of thyroid hormone can be a great way to manage the disease.
• Radioactive iodine – Injection with a dose of I-131, a radioactive iodine isotope, can effectively and often permanently decrease the function of an overactive thyroid.
• Surgery – While surgical removal of the thyroid gland has generally fallen out of favor due to the risk of complications, it is a valid option for some cats.

Cats with hyperthyroidism need to be monitored closely to be sure that their levels of hormone are kept in check and that blood pressure and kidney function are normal. Though they may require a little extra maintenance, hyperthyroid cats often go on to live healthy, normal lives.

Every feline fanatic needs to be aware of hyperthyroidism in cats. As with so many diseases, it is best managed when detected early. Routine wellness visits and screening tests may tip us off, but you know your pet best. If you have concerns about your pet or think your cat may be showing symptoms of hyperthyroidism, give us a call. We are here to help, no matter what the problem may be.