Symptoms of Addison's Disease in Cats

Hypoadrenocorticism, or Addison's disease, is rare in cats but serious or fatal if not treated, according to the Cat Health Guide, "Adrenal Glands in Cats." The cause of this deficiency in adrenocortical hormones is not always known. Autoimmune disease or cancerous tumors may destroy the adrenal gland. Sudden discontinuation of steroid medication may cause secondary Addison's disease. These hormones control metabolism. Because the symptoms are vague, it is difficult to diagnose without the assistance of a veterinarian.

  1. Symptoms May Come and Go

    • After several days of vague illness, your cat may seem to recuperate. This cycle may repeat for several months before the sickness becomes severe enough to concern you. According to Vetinfo, "7 Early Signs of Cat Illness," if your cat changes behavior or habits, it may be time to see the vet.

    Lethargy

    • It is uncommon for a healthy cat to be lethargic or weak. Addison's disease sometimes causes muscle weakness and muscle wasting. Your cat may no longer be able to jump onto its favorite perch and, instead, may spend most of the day sleeping.

    Appetite Loss and Weight Loss

    • Lack of appetite and loss of weight indicate a serious problem with a cat. However, many other conditions cause the same symptoms. You will first suspect stomach or intestinal problems, rather than Addison's disease.

    Vomiting, Diarrhea and Dehydration

    • Vomiting and diarrhea may indicate several conditions including possible poisoning. Vomiting, for a cat, may simply indicate a hairball and may be normal. When these symptoms persist or become severe enough to cause dehydration, you must seek medical help. Dehydration often causes increased waste products in the blood, causing your veterinarian to suspect kidney disease.

    Collapse

    • Your cat may suddenly go into shock or collapse. This Addisonian Crisis requires immediate medical help. If the cat responds to the usual shock treatment of IV fluids and sodium, this indicates possible Addison's disease.

    Blood Work

    • Lab tests may show low sodium and high potassium levels, mimicking kidney failure. Your cat will also have very low cortisol levels, even when given ACTH. In fact, this is how your veterinarian will finally identify Addison's disease.

    Vital Signs

    • Low body temperature is not common for a cat and signifies a serious condition. Increased potassium sometimes causes an irregular heart rhythm. Also, in Addison's disease, the heart may be smaller than normal.

    Insulin Resistance

    • According the David Brurette, in "Feline Adrenal Disease," hyperglycemia is a common lab abnormality and control of the diabetes sometimes results in normalizing the Addison's disease, even without further treatment. If your cat drinks excessive water and urinates large quantities, get veterinary help immediately.