CUSHING DISEASE

Updated: Jan 23

Most canine Cushing's disease occurs naturally and is either pituitary-dependent or adrenal-dependent. About 80–85 percent of Cushing's is pituitary-dependent, meaning it's triggered by a tumor on the pituitary, a pea-sized gland at the base of the brain.

The pituitary makes a number of hormones, including adrenocorticotropic hormone (ACTH). The pituitary tumor causes overproduction of ACTH, which travels through the bloodstream to the adrenal glands, stimulating them to produce more cortisol than the body needs.

In the other 15–20 percent of Cushing's dogs, a tumor in one or both adrenal glands produces excess cortisol.

The type of Cushing's disease may determine what kind of treatment is prescribed.

Veterinarians use blood tests to diagnose Cushing's and to differentiate between disease caused by the pituitary or the adrenals. They may also use an ultrasound to help detect a tumor on an adrenal gland.

It’s not unusual for aging canines to develop the endocrine condition known as Cushing’s disease. Formally known as hyperadrenocorticism, Cushing’s disease generally results from a benign tumor on the pituitary gland. This gland “rules” the endocrine system and produces various hormones, and the growth causes it to overproduce adrenocorticotropic hormone, or ACTH. In about 20 percent of cases, a tumor on one or both of your pet’s adrenal glands induces excess cortisol production. Cortisol is a natural steroid, but excess amounts leave your dog’s body vulnerable to all sorts of maladies.

Standard treatment for Cushing’s disease involves powerful medications which can cause serious side effects. Some of these drugs are contraindicated in dogs suffering from kidney and liver disease and other afflictions common in senior dogs.

Natural treatments are more helpful to dogs diagnosed in the early stages of hyperadrenocorticism.



Symptoms of Cushing's Disease

Cushing's disease typically occurs in middle-aged to older dogs. The disease develops slowly and the early signs are not always noticed. Symptoms in dogs include

increased thirstincreased urinationincreased appetitereduced activityexcessive pantingthin or fragile skinhair lossrecurrent skin infectionsenlargement of the abdomen, resulting in a "potbellied" appearanceconstant hungerhair thinning and lossmuscle weaknessfrequent pantingdarkening skinrecurring infectionslethargyinsomnia.

Since these symptoms mimic those of other diseases, it is crucial that you have your dog tested. A simple blood test reveals excess cortisol in your dog’s system. An ultrasound shows whether there is a tumor on the adrenal glands. Approximately half of such tumors are benign – but that means there’s a 50 percent chance of malignancy. For some dogs, surgical removal of the tumor is an option.



Treating Cushing's Disease

Vetoryl (trilostane), approved by the FDA in 2008 is the only drug approved to treat both pituitary- and adrenal-dependent Cushing's in dogs. This prescription drug works by stopping the production of cortisol in the adrenal glands. Vetoryl should not be given to a dog that

has kidney or liver diseasetakes certain medications used to treat heart diseaseis pregnant

The drug's most common side effects are poor or reduced appetite, vomiting, lack of energy, diarrhea, and weakness. Occasionally, more serious side effects, including bloody diarrhea, collapse, severe sodium/potassium imbalance, and destruction of the adrenal gland may occur, and may result in death. In 2014, with input from CVM, the manufacturer updated the information about patient monitoring and side effects on the package insert. Although not proven to be caused by Vetoryl, some additional side effects reported to CVM and now included on the package insert are adrenal insufficiency, shaking, elevated liver enzymes and elevated kidney tests.

Only one other drug, Anipryl (selegiline), is FDA-approved to treat Cushing's disease in dogs, but only to treat uncomplicated, pituitary-dependent Cushing's.

Veterinarians have often used a human chemotherapy drug, Lysodren (mitotane), "off-label" to treat Cushing's in dogs. Lysodren destroys the layers of the adrenal gland that produce cortisol. It requires careful monitoring and can have severe side effects.

"Off-label," or "extra-label," means veterinarians can legally prescribe human drugs to animals for uses not listed on the label, or for other species or at different dosage levels from those listed on the label. But because dogs may react unpredictably to human drugs, says Stohlman, it's beneficial to have treatments available that have been studied in dogs and approved specifically for them.

"Treating Cushing's is a balancing act," Stohlman says. "But dogs with the disease can live a good life if they are monitored closely by a veterinarian and the owner is diligent about bringing the dog in for blood work and checkups, watching for side effects and giving the medication as directed."


Homeopathic Pituitary

This remedy is historically made from the posterior lobe of the pituitary gland and is offered to aid in balancing the actions of the gland. It is given in low potencies (30c) over a long period of time and monitored closely.


Homeopathic Formic Acid

It has been very effective in early stages and has a history of restoring the health of the animal as well as restoring the coat. A potency of 6x has been most effective, given over a period of 1-2 months.



Supplements

Your vet can recommend supplements to help your dog fight Cushing’s disease. Common supplements that help reduce the inflammation occurring with Cushing’s disease include:

  • fish oil

  • flaxseed oil

  • glucosamine

  • turmeric

  • Melatonin may help your insomniac dog regain a regular sleep schedule.

  • Kelp

  • Nettle

  • Rosehip

  • Milk Thistle

  • Clover

  • Garlic

  • ACV (Apple Cider Vinegar)