Why Does My Dog Have Low Cortisol?


Are you worried about your dog?

Have they been behaving a bit weirdly lately with odd symptoms that can’t quite be explained?

Is your dog suddenly lacking energy or seems to be a bit anxious for no apparent reason?

Those symptoms are very common for a whole range of illnesses.

They are also symptoms of a dog with low cortisone.

Which is the condition that I want to focus on in this article.

What is cortisol and what role does it play in dogs?

Cortisol is a hormone produced in the adrenal glands.

In dogs and humans alike, it plays a part in energy production, increases blood sugar amount, regulates blood pressure, and reduces inflammation. The hormone is classified as a steroid hormone, meaning it also plays a role in stress management and energy-boosting.

What are the symptoms/side effects of low cortisol in dogs?

Symptoms of low cortisol are usually non-specific and can be similar to more common dog conditions. One of the tell-tales of low cortisol is if the symptoms worsen after stress. Here are the symptoms you should look for.

Lethargy and weakening of muscles

As stated before, cortisol is a steroid hormone related to energy. One of the common symptoms of low cortisol in dogs is fatigue.


Because cortisol is related to stress, abnormality can cause neurologic dysfunctions. This can manifest in trembling and anxiety.

Skin folds

ACTH (adrenocorticotropic) is a hormone produced in the pituitary gland at the base of the brain, it controls cortisol production. When cortisol levels are low, it triggers ACTH production. A higher level of ACTH induces melanin production, developing skin patches and skin folds.

Digestive issues (appetite loss, nausea, diarrhea, vomiting)

Like many medical conditions, low cortisol in dogs also disrupts digestion. The most common symptoms are nausea, vomiting, poor appetite, and abdominal pain. Another gastrointestinal symptom is diarrhea, but it’s less common.

Seizures or collapse

These symptoms are less common for dogs with low cortisol, but there are cases where dogs have seizures and even collapse.

High level of eosinophils

This isn’t a symptom that can be diagnosed by owners, but high eosinophils level is one of the side effects of low cortisol that vets can see after running a screening test. 

Eosinophil is a type of white blood cell. A high amount of it can mean a variety of things, including symptoms of allergies and parasite infestation, but it can also be a sign of Addison’s disease.

Anaemia (low amount of red blood cells)

Another side effect of low cortisol that’s often discovered during general diagnosis tests is a reduced amount of red blood cells. This also plays a part in why dogs with low cortisol levels experience lethargy and muscle weakening.

What causes low cortisol levels in dogs?

Low cortisol mostly happens when there’s an adrenocortical failure. It’s unknown what causes the adrenal glands to malfunction, but it’s predicted to be caused by an autoimmune disease, hemorrhage, tumor, or enzyme inhibition.

Low cortisol levels can also be triggered by stress. As stated before, cortisol also has a role in stress management. Every time the body is in danger and/or experiences stress, when the stress goes down, cortisol levels go down.

The problem arises when your dog is constantly under stress. The cortisol levels will be down all the time, and the body’s functions might get damaged.

What are the best ways to help a dog with low cortisol levels at home?

Low cortisol levels can’t be treated naturally at home, but there are some things you can do to help the situation. Mainly, you need to lower your dog’s stress levels, both emotionally and biologically. 

High quality foods and supplements

To reduce biological stress, one of the best ways is of course by giving your pup high quality nutritious foods. This usually means easily digested animal-source foods and avoidance of grainy ingredients.

Probiotics are another good way to improve your dog’s food quality. For dogs with digestive symptoms, give them digestive enzyme powders.

You can also buy off-the-counter dog food supplements. There are many supplements specifically labeled to be for “canine adrenal support.”

Minimize emotional stress

For emotional wellness, don’t confine them and play with them regularly. Know what distresses your dog and avoid them as much as you can.

Medicinal herbs

Sometimes, medicinal herbs are used to relax or sedate dogs with Addison’s. Herbs like licorice or German chamomile can be brewed as tea, added to food, or applied to the skin and coat to help them relax.

What is Addison’s disease and is it life-limiting?

The condition of having low cortisol levels is called Addison’s disease. The term is used synonymously with hypoadrenocorticism (HOAC), which is a broader term defining the state of adrenal glands producing a low amount of hormones (it can also be hormones other than cortisol). The medical name for Addison’s in dogs is canine hypoadrenocorticism.

Sometimes, Addison’s is accompanied by a low level of aldosterone, another hormone made in the adrenal glands.

While at first the symptoms of the disease might come and go, Addison’s disease is actually a serious condition. If left untreated for too long, it can result in death.

Thankfully, once a dog gets diagnosed with Addison’s disease, they can quickly be treated by the vet. However, the treatment is usually life-long. If you see symptoms of Addison’s on your dog, quickly take them to the pet hospital.

How is Addison’s disease diagnosed?

Addison’s disease can be tricky to diagnose because its symptoms are easily confused with other common dog diseases. Because of this, Addison’s is dubbed “the great pretender.”

A diagnosis is usually made when the disease is at an acute stage, and the dog begins experiencing an Addisonian crisis. At this stage, the dog will show worrying symptoms like shock and collapse.

  • Baseline cortisol screening test

The vet will run a specific screening test for Addison’s disease called baseline cortisol. However, this test is done to eliminate the possibility of Addison’s, and not to diagnose the disease itself.

  • ACTH stimulation test

If the baseline cortisol test results come back low, the vet will then do an ACTH stimulation test.

For an ACTH stimulation test, your dog will be injected with Cortrosyn (a synthetic hormone specifically used to screen adrenocortical insufficiency). They will compare the amount of cortisol before and after the Cortrosyn injection. If the cortisol level doesn’t increase after injection, it means the dog has Addison’s disease.

  • CAR test (Cortisol to ACTH Ratio)

Other than ACTH stimulation, there’s another alternative used to diagnose low cortisol called a CAR test. Instead of injecting a synthetic hormone, CAR test simply compares cortisol level to ACTH level. If the ACTH concentration is high but the CAR is low, it’s a sign of Addison’s.

ACTH stimulation is used more often than CAR test because it only measures one hormone. On the other hand, to run a CAR test they would need to measure both cortisol and ACTH. However, CAR test is more definitive to diagnose Addison’s disease compared to ACTH stimulation.

How to treat Addison’s disease in dogs?

Initial treatment for Addison’s in dogs after diagnosis

If Addison’s disease is diagnosed after an Addisonian crisis, the vet will give initial treatments to remedy the crisis. Your dog will go through intensive therapy to treat all of the critical symptoms.

What is the most effective treatment for Addison’s disease?

The most effective and most commonly used treatment for low cortisol in dogs is the administration of synthetic cortisol called corticosteroids. There are several types of corticosteroids including glucocorticoids and mineralocorticoids.

The most common corticosteroid treatment used for Addison’s disease in dogs is DOCP (Desoxycorticosterone pivalate). DOCP is a mineralocorticoid medication, and some of the popular brands of DOCP are Zycortal and Percorten-V.

It’s injected into the veins and is FDA-approved for dogs. Treatment is given only about once in 3-4 weeks. At first, it’s done at the vet, and then the vet will teach the dog owners how to give the treatment themself at home.

DOCP injections are sometimes accompanied by a supplement of oral glucocorticoid. If your dog isn’t responding well to DOCP, you can replace the DOCP altogether with oral medications in place of both mineralocorticoid and glucocorticoid. An example of this oral medication is fludrocortisone.

What dogs are most vulnerable to Addison disease?

In dogs, Addison’s disease is more prevalent in females than males. Around 70% of the afflicted are female dogs.

Interestingly, unlike most diseases, Addison’s disease tends to strike younger or middle-aged dogs more than the old ones. For typical hypoadrenocorticism (symptoms of low cortisol level and electrolyte abnormalities), dogs at age 4 are at higher risk.

On the other hand, atypical hypoadrenocorticism (low cortisol but normal electrolyte levels), afflicts dogs between 6-7 years of age more than the rest.

The good news is that Addison’s disease in dogs isn’t a common condition. On the opposite side of the spectrum, Cushing’s disease (a condition of cortisol overproduction) is more common.

Are certain breeds more vulnerable than others?

Researchers have found that Addison’s disease can be hereditary for several dog breeds that are more at risk. Some dog breeds that have a higher risk of hereditary low cortisol levels are:

  • Nova Scotia duck tolling retrievers (NSDTR)
  • Standard Poodles
  • Portuguese Water Dogs

There are also breeds that have a higher risk of Addison’s disease but haven’t been proven to be hereditary, including:

  • Bearded Collies
  • Rottweilers
  • Great Danes
  • West Highland White Terriers
  • Cairn Terriers
  • Labrador Retrievers
  • Great Pyrenees
  • Pomenarians
  • Golden Retrievers
  • other Poodles
James Grayston

My name is James and I love dogs. have owned four Golden Retrievers in the past 15 years. Currently I own two "Goldies"- a five year old and a seven month old. The photo shows me with our youngest when she was about 7 weeks old!