Tuesday, Nov. 4, 2008
K-STATE VETERINARIAN SAYS NEW DRUG IS AVAILABLE FOR DOGS WITH CUSHING'S DISEASE, BUT CAUTIONS THAT TREATMENT CAN BE COSTLY
MANHATTAN -- A new medication is available to treat dogs with Cushing's disease, but pet owners should be prepared for the cost of managing the disease, according to a veterinarian at Kansas State University's College of Veterinary Medicine.
Dr. Kenneth Harkin, associate professor of clinical sciences, said a new drug called Trilostane is undergoing approval by the Food and Drug Administration, but veterinarians may obtain the medication if they decide it is the necessary choice to treat Cushing's disease.
The disease is the result of the dog's body producing too much cortisol, the steroid that is important for the body’s stress response. Harkin said the excess cortisol is either caused by a tumor of the adrenal gland or, more commonly, of the pituitary gland. He said if the Cushing's disease is caused by an adrenal gland tumor, veterinarians usually try to remove the tumor. If it's a more common pituitary gland tumor, veterinarians rely on medication.
Harkin said that Trilostane, which comes in a twice-daily pill, works by inhibiting an enzyme that turns cholesterol into cortisol. This drug presents an alternative to medications that treat Cushing's by destroying the adrenal gland, he said.
The problem with producing too much cortisol, Harkin said, is that it causes muscle wasting, can increase the susceptibility to infection, may delay healing, and, at a minimum, can cause clinical signs that are annoying. These can include excessive thirst and urination, a ravenous appetite, excessive panting and an appearance that is displeasing, such as a potbelly, hair loss and thin skin. The potbellied appearance from Cushing’s disease is different than in an obese dog, however.
"An overweight dog will have full hips and back," he said. "With Cushing's, they have muscle loss on the hips and legs, too."
Although the surplus of cortisol is destructive to the dog's body, the excess steroid is making the animal feel quite well.
"You see these dogs with Cushing's disease that look awful, but they feel great," Harkin said.
Cushing's disease, which is not common among humans, is comparatively prevalent in dogs, Harkin said. It's a disease that usually impacts older dogs -- those 8 years old or older -- although dachshunds seem to be particularly vulnerable at a young age, he said.
Although Cushing's is a manageable disease, Harkin said dog owners should be aware that it is costly to treat.
"What pet owners need to recognize is that it's not cheap to treat Cushing's disease," he said. "It is a financial commitment for the owner."