Elevated Cortisol Levels in Dogs: Understanding and Managing
Has your dog been drinking their water more quickly than usual even with extra refills? Or maybe your housetrained pooch had an accident or been requesting extra night time potty breaks? Perhaps you’ve also noticed your pup devouring every meal with even more than their typical enthusiasm. All of these indicators may be clinical signs pointing to the possibility of elevated cortisol levels in your dog.
Elevated cortisol levels usually occur in middle aged or senior dogs. Cortisol is a very useful and necessary hormone that helps with stress response, metabolism, and many other important bodily functions. However, excess cortisol can impair the immune system and often leads to serious health issues.
Types of Elevated Cortisol Levels
Most cases of elevated cortisol levels in dogs happen because of tumor development in either the pituitary or adrenal gland. A gland tumor in either one of these locations stimulates the adrenal glands, and generates excess cortisol production
Instead of being caused by pituitary tumors, adrenal-dependent elevated cortisol levels are the result of adrenal tumors. An adrenal gland tumor would be located in one of the adrenal glands above each kidney and may affect production of an array of hormones regulating an array of essential functions. Around 15% of elevated cortisol level occurrences in dogs are this adrenal variety.
The final type occurs as the direct result of a dog taking steroids for an extended time period. Although originally prescribed by a veterinarian, prolonged use of these steroids also elevates cortisol levels above the healthy range, leading to serious issues. Because this type of elevated cortisol levels is resolved with cessation of steroid medication, we will not be further exploring this type.
Breeds with Higher Risk
While a direct link has not been scientifically proven, the risk of elevated cortisol levels may be influenced by genetic factors and breed differences. Breeds prone to developing this issue include:
- German Shepherds
- Yorkshire Terriers
- Labrador Retrievers
- Cocker spaniels
- Australian shepherds
Signs of Elevated Cortisol Levels in Dogs
Because the production of cortisol impacts a wealth of biological processes, the familiar signs and symptoms of these issues are also many in number and often come on slowly, cushion’s is frequently misattributed to other health conditions.
Common symptoms include:
- Drinking more water and faster than usual
- Urinating - dogs may have accidents inside despite being housebroken
- Thin skin/skin infections
- Hair loss
- Increased appetite
- Pot belly
- Heavy panting
- High blood pressure
- Impaired immune system and increased risk of infection
If your pup shows any of these symptoms or warning signs of potentially major issues, contact your veterinarian promptly, so they can determine whether medical treatment is necessary.
Identifying Elevated Cortisol Levels in Dogs
Before starting a veterinary treatment plan, an accurate diagnosis must be made for your dog. Although there is not a single method for diagnosing elevated cortisol levels in dogs, a veterinarian will usually start with blood and urine tests. The amount of cortisol regularly fluctuates, so diagnosing is not as straightforward as simply measuring the quantity of cortisol present in your dog's blood.
Types of Diagnostic Testing for Elevated Cortisol Levels
Cortisol levels regularly fluctuate, so diagnosing this issue is not as straightforward as simply measuring the levels of cortisol in your dog's blood. An integrated approach may be necessary, and your vet will likely combine several examination methods along with the symptoms you’ve reported in order to reach their final diagnosis.
- ACTH Stimulation Test - measures cortisol before and after injection with adrenocorticotropic hormone to determine that adrenal gland and pituitary gland functions produce the hormone normally. In healthy animals, there will be an increase.
- Low Dose Dexamethasone Suppression Test - measures levels of the stress hormone before and after injection with dexamethasone to determine whether pituitary and adrenal gland response is normal. This test is like the reverse of the ACTH stimulation test because a decrease occurs in healthy dogs.
Managing Pituitary and Adrenal Tumors
Advances in internal medicine have greatly increased the array of veterinary options and methods used to manage elevated cortisol levels in dogs. Your dog’s care may include surgery, medication, radiation, or a combination of these methods.
Surgical removal is the only method known to “cure” elevated cortisol levels in dogs, but this procedure is often very complicated, resulting in additional risks to the animal. For adrenal dependent cases, a complete excision of the affected adrenal gland including the adrenal tumor is performed. For pituitary dependent cases, a surgery called hypophysectomy to remove the pituitary tumor is gaining popularity as a viable treatment although it may cost up to $10,000.
Most veterinarians still prefer addressing and managing both types in dogs with medication. The two most common medicines for managing elevated cortisol levels include:
- Trilostane was the first prescription approved by the FDA for elevated cortisol levels in dogs and works in the adrenal glands to halt production of stress hormones. Vetoryl has been approved to treat both adrenal dependent and pituitary dependent forms of this disease, but may not be an option for dogs with kidney/liver issues or an active pregnancy.
- Mitotane is an anti-cancer medication that vets often prescribe "off label" in caring for cushing’s syndrome dogs.
Continued veterinary check-ups and vigilant monitoring through blood tests and adjusting medication is crucial to increase an animal’s prognosis. Dosage will likely need to be adjusted over time as the tumor develops as well as to mitigate any side effects.
Quality of Life for Dogs with Elevated Cortisol Levels
Once identified and under veterinary care, many dogs with elevated cortisol levels go on to live happily and comfortably for years. Sometimes medications may result in unpleasant side effects for your dog, but your pet’s overall health will be much better than a dog with an undetected gland tumor.