Hyperthyroidism is one of the most mystifying diseases in all of modern veterinary medicine.
Over the last fifty years, hyperthyroidism has grown from a disease that no one – not even trained vets – had ever heard of to one of the leading afflictions of senior cats today. Scientists aren’t exactly sure why.
What is Hyperthyroidism in Cats?
The thyroid gland is a hormone-producing gland that sits at the base of mammals’ necks. In animals with hyperthyroidism (also called “thyrotoxicosis”), the gland over-produces the hormones T3 and T4, which results in a litany of uncomfortable symptoms. Since the thyroid gland affects almost every organ in the body, the results of hyperthyroidism are devastatingly widespread.
In almost all cats with hyperthyroidism, a non-cancerous tumor called an “adenoma” causes the enlargement of the thyroid gland which in turn ramps up hormone production. In a very small number of cases, malignant tumors are to blame.
Hyperthyroidism almost exclusively affects cats (not dogs), although dogs are at a far greater susceptibility for hypothyroidism, which is an underactive thyroid. The condition is so common in cats that it is recommended all cats over 7 years old be screened by a veterinarian annually.
The Signs of Hyperthyroidism in Cats
Hyperthyroidism almost always affect cats that are middle-aged or older. Symptoms are typically subtle at first, increasing with time, and include:
- Dramatic weight loss (even with normal eating)
- Increased appetite and/or thirst
- Increased urination
- Diarrhea and/or vomiting
- Greasy, unkempt-looking coat
Over time, the condition can make a cat incredibly uncomfortable. Weight loss can cause stiffness to the joints, and kidney failure can result as the cat’s body works to process blood. Eventually, heart failure can occur if hyperthyroidism is not treated.
Can Hyperthyroidism be Treated?
The good news is, it is relatively straightforward for your vet to test your cat for hyperthyroidism. If symptoms are obvious, your vet may be able to feel your cat’s enlarged thyroid gland through her skin. In most cases, diagnosis is obtained after a simple blood screening which checks for elevated levels of thyroid hormones, particularly T4.
There are actually several treatments available for feline hyperthyroidism; the best treatment for each cat is determined on an individual basis. Treatment options include medication, diet change, surgery, and in severe cases, radioactive iodine therapy. Some treatments attempt to treat the thyroid tumor itself which is the underlying cause of the disease. Others simply stem the flow of thyroid hormones to the body, curtailing the harmful side effects.
If treated early, cats with hyperthyroidism can live long, healthy lives. It is imperative if you suspect your cat may be suffering from a hormone imbalance that you contact your veterinarian immediately.
If she is seven years old or older, you’re overdue. Reach out to a vet today to schedule a quick, easy screening.