An endocrine disease is any condition involving hormones. The most common one in cats is hyperthyroidism. Affecting at least 10 percent of cats age 10 and older, it is an illness in which the thyroid glands, one on each side of the feline neck, produce too much of the thyroid hormones that regulate metabolism and thereby speed up that process. Left uncontrolled, hyperthyroidism can lead to a cat becoming perilously emaciated no matter how much she eats. Heart rate can speed up, too, leading to heart disease.
Because of the dangers that come with the condition, the American Animal Hospital Association has just released new guidelines advising that cats with the disease be seen every six months — more frequently if they also have other significant illnesses. That will allow veterinarians to elicit information from a client about how the pet is doing, which can help guide decisions about adjustments in medication dosages.
Other endocrine (hormonal) diseases of cats include hypothyroidism (too little in the way of thyroid hormones), hyperaldosteronism (an imbalance in the secretion of aldosterone, which regulates sodium and potassium levels), and hypercortisolism (excess production of the hormone cortisol, which can lead to muscle wasting and weakness).