What is adrenal insufficiency?

Medically reviewed by Neka Miller, PhD on January 12, 2020. To give you technically accurate, evidence-based information, content published on the Everlywell blog is reviewed by credentialed professionals with expertise in medical and bioscience fields.

Because cortisol—the body’s “stress hormone” that’s responsible for regulating your stress response and other key functions—is produced in the adrenal glands (located above your kidneys), adrenal gland issues can lead to a decrease in cortisol production and ultimately result in a condition known as adrenal insufficiency.

Want to learn more about what adrenal insufficiency is and how to tell if you may be experiencing symptoms of decreased cortisol production? Read on as we break down what you need to know about adrenal insufficiency below.


What is adrenal insufficiency?

Adrenal insufficiency (AI), or hypocortisolism, is a condition in which the adrenal glands fail to produce enough cortisol to perform important functions in the body. Although all forms of adrenal insufficiency are generally associated with deficient cortisol production, AI has 3 different categories:

Primary adrenal insufficiency (Addison’s disease): A condition resulting from damage to the adrenal cortex, preventing the adrenal glands from properly functioning and leading to decreased cortisol production. In the United States, it’s most commonly caused by immune system malfunction, but other possible causes include infection and cancer.

Secondary adrenal insufficiency: A condition caused by the pituitary gland (the “master gland” in your brain that produces several hormones) failing to secrete enough adrenocorticotropic hormone (ACTH)—the hormone that tells the adrenal glands how much cortisol is needed in the body. This lack of communication between the pituitary and the adrenal glands causes a decrease in cortisol production.

Tertiary adrenal insufficiency: A condition where the hypothalamus (the region in your brain that links the nervous system and the endocrine system through the pituitary gland) releases an inadequate amount of corticotropin-releasing hormone (CRH)—the hormone that tells the pituitary gland to produce ACTH.

The Everlywell Sleep & Stress Test lets you check how your cortisol levels (as well as cortisone and melatonin) fluctuate over a 24-hour period, which may help provide insight into what may be causing sleep problems, whether you may be experiencing chronic stress, and more. The process is as simple as collecting your urine samples at home, sending them to a CLIA-certified lab using the prepaid mailer included with the kit, and getting your digital results in days. Note that this test does not diagnose adrenal insufficiency.

What is the most common cause of adrenal insufficiency?

There are many possible causes of adrenal insufficiency, including autoimmune disease, genetic mutations, infections, and steroid treatment intended for other conditions such as asthma and cancer.

Below we break down some of the most common causes of adrenal insufficiency for each category.

Common causes of primary adrenal insufficiency (Addison’s disease)

Primary adrenal insufficiency is often a result of genetic factors that impact the development or function of the adrenal glands. However, Addison’s disease can also be caused by:

  • Cancerous cells in the adrenal glands
  • Surgical removal of the adrenal glands
  • Certain antifungal medications

Common causes of secondary adrenal insufficiency

  • Autoimmune disease
  • Pituitary tumors or infection
  • Pituitary bleeding
  • Genetic diseases affecting pituitary gland development or function
  • Removal of the pituitary gland through surgery
  • Traumatic brain injury

Common causes of tertiary adrenal insufficiency

  • Abruptly coming off corticosteroids
  • Cushing’s syndrome (tumors in the pituitary or adrenal glands that produce excess amounts of ACTH or cortisol)

Want to learn more about how to tell if you may be experiencing a form of AI? Read more about the signs of adrenal insufficiency below and find a more detailed breakdown in our post about adrenal insufficiency symptoms.

What are the symptoms of adrenal insufficiency?

Just like with the possible causes listed above, the symptoms of adrenal insufficiency can show up in different ways.

Symptoms of primary adrenal insufficiency (Addison’s disease)

Before we list the signs and symptoms of primary adrenal insufficiency, it’s important to note that Addison’s disease is a very rare condition in developed nations, impacting approximately 100 to 140 people per million in developed countries.

Often, symptoms of primary adrenal insufficiency develop slowly and it takes an illness or injury to shine a light on the disease, as symptoms may worsen during this time.

Signs and symptoms of Addison’s disease may include:

  • Extreme fatigue
  • Weight loss
  • Dehydration
  • Decreased appetite
  • Irritability
  • Depression
  • Hyperpigmentation, which often starts in parts of the mouth
  • Low blood pressure
  • Fainting
  • Craving for salt
  • Hypoglycemia (low blood sugar)
  • Nausea
  • Diarrhea
  • Vomiting
  • Pain in the abdomen
  • Muscle or joint pains
  • Loss of body hair
  • Menstrual cycle irregularities

Symptoms of secondary and tertiary adrenal insufficiency

The symptoms of secondary and tertiary adrenal insufficiency are similar to those of Addison’s disease with some of the key differences including:

  • Hyperpigmentation and dehydration do not occur
  • Blood pressure issues are less common
  • Low blood sugar levels are more common

How is adrenal insufficiency diagnosed and treated?

An adrenocorticotropic hormone test, or ACTH stimulation test, can help identify if you may be experiencing primary or secondary adrenal insufficiency (AI). If your results indicate that you are indeed experiencing this, your healthcare provider may prescribe medicines to replace the hormones that your body—specifically, your adrenal glands—aren’t making.

What are cortisol levels?

Cortisol levels and stress: how cortisol levels and stress are connected

Cortisol and sleep: Do cortisol levels affect sleep?


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