Alternative and dietary treatments for Cushing’s Disease
Cushing’s Disease, also known as Cushing’s syndrome or hyperadrenocorticism, is a condition in which the body produces too much of a type of steroid called cortisol. This can be caused by a tumor in the adrenal glands (the glands that produce steroids in the body) or the pituitary gland in the brain (the pituitary gland tells your adrenal glands when to produce steroids and how much to produce).
When the tumor is in the pituitary gland, it is called pituitary dependent hyperadrenocorticism. When the tumor is in the adrenal gland, it is called adrenal dependent hyperadrenocorticism. There is a type of Cushing’s called atypical Cushing’s, which is controversial – some people believe it exists, others don’t. Atypical Cushing’s is caused by an increase in different types of steroids from cortisol – usually the sex hormones like estradiol or estrogen. It is controversial, because nobody has proven that these increases actually cause the clinical signs.
Usually, the tumor in the pituitary gland is so small that the only problem it causes is Cushing’s Syndrome. Rarely, it can be a big enough tumor to cause other neurological (brain) problems. The adrenal gland tumor can cause other problems and can be benign or malignant (cancerous). It can get big enough to invade the nearby blood vessels and it can spread. Sometimes, though, all it does is produce excess steroids.
Clinical signs of Cushing’s syndrome can be similar to many other diseases. Dogs with Cushing’s syndrome drink a lot, urinate a lot, eat a lot, gain weight, pant more than usual, and have skin issues. A dog may have all of these signs or just a few, depending on when the disease is found and how severe the elevation in cortisol.
Cushing’s Syndrome is both over-diagnosed and under-diagnosed, because the clinical signs can mimic so many other conditions (such as kidney disease, heart disease, diabetes). The thing that sets Cushing’s Syndrome apart is that the patient is not acting sick – in fact, they feel quite well due to the excess cortisol. If your pet is sick in any other way (cancer, kidney disease, vomiting, diarrhea) they may test positive for Cushing’s Syndrome because their cortisol levels are high to deal with the illness. Testing for Cushing’s is almost never an emergency – it is best to wait until your pet is no longer actively sick before testing for it.
The treatment of choice for adrenal gland tumors is surgery – removing the adrenal gland with the tumor in it should be curative. This is also beneficial since about 50% of the adrenal gland tumors are malignant. The treatment of choice for pituitary dependent Cushing’s is medication. The most commonly used drug is called trilostane (brand name Vetoryl). This medication interferes with the enzymes that help produce cortisol, causing the cortisol levels to drop. It is quite safe, but it can cause problems such as decreased appetite, lethargy, vomiting, and diarrhea. It will cause the adrenal glands to get bigger over time – this is not a problem in and of itself, but may mean that the adrenal glands look abnormal on ultrasound. Sometimes, if the dosage is too high, the dog can develop Addison’s, which is the opposite of Cushing’s (a lack of steroids) and can be life threatening if not caught early.
In my experience, many dogs do not feel good on the typical dosages of trilostane and can actually be better regulated on much lower dosages than those previously reported. We monitor the success of trilostane with periodic blood work (ACTH stimulation test or cortisol levels) to see if the levels are where we want them to be. Even when the levels are good, we sometimes still see clinical signs of Cushing’s, including excessive drinking and urinating, excessive appetite, panting, and weight gain.
Other medications were previously used, including selegiline (anipryl) and lysodren (mitotane). Anipryl was FDA approved for use in Cushing’s Disease, but we have found that it doesn’t actually decrease the cortisol levels – it simply makes the dog feel better by increasing dopamine in the brain. Lysodren is quite effective. This is a medication that actually kills off the portion of the adrenal gland that is producing too much cortisol. While it is effective, it has a greater potential of being too strong for patients, and the risks of developing a life threatening decrease in cortisol is much higher than it is for trilostane.
Many people ask about more natural or holistic treatments for Cushing’s Disease. In general, these treatments are more likely to be successful in mild cases of the disease. Most dogs end up needing trilostane eventually, but you may be able to delay the start of treatment with these holistic remedies. There are no large studies examining the use of alternative therapies for Cushing’s Disease and comparing them to traditional methods. It is always important to work with your veterinarian to discuss any treatment plans prior to starting them. There are integrative veterinarians who are trained in Chinese medications, herbs, acupuncture, and nutrition. If your pet is diagnosed with Cushing’s, you can try changing to a well-balanced, home cooked diet.
This can help decrease sodium levels and also help decrease excessive drinking and urinating. Herbs can be helpful, but it is important to work with an integrative veterinarian to find the right combination. Some herbs that are safe to use include fish oils or other antioxidants (these decrease oxidative damage due to cortisol). Gingko balboa may help decrease cortisol release, and dandelion root helps maintain/restore adrenal gland function. Acupuncture may help increase mobility and increase energy, but does not necessarily decrease cortisol. Melatonin and lignans have been recommended for patients with atypical Cushing’s – their success varies based on how severe the clinical signs are.
Left untreated, Cushing’s Disease can lead to problems such as loss of muscle mass, high blood pressure, protein in the urine, decreased resistance to infections, skin problems (depositing calcium into the skin called calcinosis cutis), and overall decreased quality of life. If you choose to try alternative medications, make sure to work closely with your veterinarian and consider traditional medications if the clinical signs are worsening or your dog is not doing well.