Q: I have a 12 year old female Boston Terrier, Charlie, who has recently been drinking loads of water and urinating in the house, and steals food from the other dog and cat and even from the dinner table! My vet feels she may have Cushing’s disease. He offered radiation therapy, but I have been trying some homeopathic products like Cushex drops from Petalive.com. It doesn’t seem to be working. Can you comment?
A: I can sympathize with your situation with Charlie drinking and urinating so much (polydipsia and polyuria), along with excessive hunger (polyphagia), all of which are among the most common symptoms we see with Cushing’s disease due to an excessive amount of cortisol production from the adrenal gland(s). Other common problems include muscle weakness, hair loss, urinary or respiratory infections from a suppressed immune system, and a potbellied appearance from tremendous liver enlargement. The diagnosis of Cushing’s disease is usually confirmed with hormone testing (ACTH stimulation or low dose dexamethasone suppression testing), before any treatments are administered. It is one of the most common endocrinopathies (glandular diseases) we see in older dogs.
Because most of the dogs are older and often have concurrent medical conditions, the workup prior to treatment includes basic blood chemistries and urinalysis, chest radiographs, urine culture, abdominal ultrasound, and blood pressure testing. Pituitary dependent Cushing’s disease (PDH) is the most common form of the disease. In this form of the disease a small tumor (adenoma) exists in the pituitary gland located at the base of the brain. Occasionally Cushing’s disease is due to a tumor in the adrenal gland instead of the pituitary gland.
The most common treatments for Cushing’s disease are medical for PDH, and surgical for a single adrenal mass. In the very rare instance of a pituitary macroadenoma, identified by MRI imaging, radiation therapy is recommended. Although it requires close monitoring, medical therapies are usually very successful in controlling the symptoms of Cushing’s disease and improving the quality of life for both the patient and the pet owner. Lysodren (generically known as mitotane) has been the traditional medical therapy until recently. It directly destroys the part of the adrenal gland responsible for the production of cortisone. I was involved in a multi center study to test a drug called trilostane on newly diagnosed Cushing’s disease patients or patients who had not responded well to Lysodren. Trilostane is now available in the US, marketed under the name Vetoryl. Trilostane is an inhibitor of an enzyme involved in the production of several steroid hormones including cortisol. I now use trilostane almost exclusively for the treatment of Cushing’s disease in dogs, and I have been extremely pleased with the results. Although both drugs can have side effects and require frequent monitoring, trilostane appears to be handled better by most patients.
I would consider seeking the advice of a veterinary internist as to the type of Cushing’s disease Charlie may have and the possible therapies to address it. PDH due to a macroadenoma requiring radiation therapy would be an extremely rare condition. I have not found holistic therapies to be of use in the management of this condition, but have been very pleased in the response of most patients to medical or surgical therapies. Except in very rare circumstances, the diagnosis and treatment is not considered a medical emergency. Although fatal complications from Cushing’s disease can occur, the condition is usually a chronic one, and some patients may go for years untreated. Best of luck with Charlie and I hope she does well!