What is Addison’s Disease?

Addison’s disease is a rare endocrine condition where the adrenal glands cease to function, so that your body no longer produces enough of certain essential hormones, known as steroid hormones. The adrenal glands are small triangular shaped glands that sit on top of your kidneys. Their job is to produce the hormones that keep the body functioning properly. 

Fortunately, you can replace these essential hormones with daily steroid tablets. The hormones that your body no longer produces enough of are:

  • Cortisol, aldosterone and DHEA (for “primary adrenal insufficiency” or Addison’s disease)
  • Cortisol and DHEA (in the case of “secondary adrenal insufficiency”)

Cortisol regulates appetite, blood sugar and food metabolism; aldosterone regulates sodium, fluid balance and blood pressure; DHEA influences body hair growth and libido (sex drive).

With the right balance of daily medication, people with Addison’s can expect to have a normal life span. It is not unknown for people with Addison’s to live into their 90s. Perhaps the most famous person with Addison’s was US President John F Kennedy.

What causes adrenal insufficiency? 

In people who have adrenal insufficiency, the adrenal glands stop working properly and aren’t able to produce hormones which are crucial to keeping our body functioning correctly. Adrenal insufficiency has multiple causes, giving three different types of adrenal insufficiency: primary (adrenal), secondary (pituitary), and tertiary (hypothalamus). The type of adrenal insufficiency (primary, secondary or tertiary) depends on whether the problem lies in the adrenal gland or is due to impairment of the hypothalamus and pituitary gland.

We often hear from people who are confused as to what the terms primary, secondary and tertiary adrenal insufficiency mean – and for good reason! Below we provide an overview of the three types.

Addison’s disease (also called primary adrenal insufficiency). This is where the adrenal glands themselves stop working – no cortisol is produced. There is also the loss of the mineralocorticoid aldosterone and this is why people with primary adrenal insufficiency (Addison’s) also take the medication fludrocortisone.

Often Addison’s is caused by the body’s immune system making a mistake and attacking and destroying the cells of the adrenal glands in error. This type of Addison’s is called autoimmune Addison’s. Addison’s can also be caused by an infection (such as tuberculosis or HIV) damaging the adrenal glands. Occasionally, a person may need to have their adrenal glands removed. This is called a bilateral adrenalectomy and is another cause of primary adrenal insufficiency. There is also the loss of the sodium retaining hormone or mineralocorticoid aldosterone and this is why people with primary adrenal insufficiency (Addison’s) take the medication fludrocortisone.

Secondary adrenal insufficiency. Here the problem lies in the pituitary gland. The pituitary is a small pea sized gland in your head that produces a hormone called ACTH that tells your adrenal glands what to do. If the pituitary gland stops sending these hormone signals, the adrenal glands don’t work properly and can’t produce the hormone, cortisol. People with this condition usually still produce aldosterone, meaning they usually have fewer problems with low blood pressure and disturbed salt levels than people with primary Addison’s disease.

And then finally there is also a third category, tertiary adrenal insufficiency, where the problem lies in the hypothalamus. This is often where exogenous glucocorticoids are administered, usually for the treatment of inflammatory conditions. This needs to be handled differently to secondary AI as it is a common problem and it is possible that the adrenal glands will recover, whereas in other forms of primary and secondary AI recovery is not possible. Separating secondary from tertiary can be difficult and secondary and tertiary are often placed together under the secondary title.

Genetic causes. In some people, there is a mistake in the spelling in their genetic code, meaning the adrenal glands are unable to manufacture the necessary hormones. One such condition is congenital adrenal hyperplasia (CAH), where there is a spelling error in the gene responsible for producing a protein that helps to generate cortisol in the adrenal glands; as a result, cortisol and often aldosterone levels are low. Another condition that causes of adrenal insufficiency is X-linked adrenoleukodystophy (ALD) or adrenomyeloneuropathy (AMN). This affects boys and men and can cause both adrenal insufficiency and neurological symptoms. 

Some people with Addison’s also have an Autoimmune Polyglandular Syndrome meaing they could also be diagnosed with other autoimmune conditions. 

While the different types of adrenal insufficiency listed above have different causes, people who live with them day-to-day experience similar challenges regarding their steroid dependency, resulting from the inability of their adrenal glands to produce cortisol. They need to take steroid medication every day to stay healthy.

Much of the information on this website – particularly regarding steroid treatment and emergency experiences – is relevant to people who are steroid-dependent from any cause of adrenal insufficiency, not just those with primary Addison’s Disease.

How common is Addison’s disease?

Addison’s disease affects approximately 1 in 10,000 people, meaning an estimated 300 – 350 new cases are diagnosed each year across the UK. This makes it roughly 300 times rarer than diabetes, another endocrine condition that sometimes occurs alongside Addison’s. Diagnosis is most common between the ages of 30 – 50, but can occur at any age.

What are the signs and symptoms of Addison’s disease and adrenal insufficiency?

People with adrenal failure typically report some or all of the following symptoms:

  • overwhelming exhaustion
  • weakness
  • weight loss
  • deepening skin pigmentation (looking like they a sun tan even when they haven’t been out in the sun)
  • dizziness on standing
  • low blood pressure
  • poor appetite
  • nausea or vomiting
  • difficulty concentrating
  • muscle weakness with cramps
  • salt cravings
  • headaches
  • stomach pains

As it can be an autoimmune condition, people with Addison’s disease may have other autoimmune conditions either themselves or present in their immediate family. These can include thyroid disorders, diabetes, vitiligo, coeliac disease or B12 deficiency.

How is Addison’s disease and adrenal insufficiency diagnosed?

Diagnosis is done by hospital blood tests and an assessment of the symptoms. Suspected cases will be referred to see an endocrinologist, a doctor who specializes in treating hormone-related conditions.

The main blood test used is called the short Synacthen test (also known as an ACTH stimulation test or a cosyntropin test). This measures the ability of your adrenal glands to produce cortisol and involves two blood samples being taken. The first is a ‘baseline’ reading to measure how much cortisol is in your blood when at rest. You are then given an injection of a hormone called ACTH (this is the hormone normally produced by your pituitary gland to instruct your adrenal glands what to do) and a second blood sample is taken 30-60 minutes after this. If the adrenal glands are healthy, cortisol production in the second sample will exceed a certain level, commonly 500-550 nmol/L. By contrast, adrenal glands that aren’t working properly will not be able to produce this amount of cortisol.

Additional hospital blood tests will measure your aldosterone function. These are plasma renin, sodium & potassium tests. A further antibody blood test to establish the cause of your adrenal failure is recommended. If this is negative, an adrenal scan and other tests may be needed.

How is Addison’s disease and adrenal insufficiency treated?

People with Addison’s disease will need to take daily steroid medication to keep their bodies functioning well for the rest of their lives. This medication replaces the hormones that their adrenal glands can no longer make.

Most people take their steroid medication three times a day, starting when they first wake up and then at five to six hourly intervals in the day. The amount and type of medication varies a lot from patient to patient and depends upon the type of adrenal insufficiency they have been diagnosed with and their individual needs. Together with their endocrinologist, they should work out a medication schedule that suits them.

Common medications include:

  • Hydrocortisone: this medication is given to replace cortisol and is usually taken in three divided doses throughout the day
  • Fludrocortisone: this medication replaces aldosterone and is usually taken in one or two daily doses
  • Dehydroepiandrosterone (DHEA): this medication is another hormone that is produced by the outer layer of the adrenal gland, the cortex. It influences stamina and libido and is a precursor hormone. DHEA is not taken by everyone living with Addison’s.

An adrenal crisis is a medical emergency – always be prepared

We strongly recommend people with Addison’s and adrenal insufficiency, so are steroid-dependent, always keep the following 4 items on them: 

  1. Hydrocortisone medication,
  2. Emergency hydrocortisone injection kit,
  3. Medical alert bracelet, and
  4. Steroid alert card.

A prescribed emergency injection kit is required in case of adrenal crises. This kit is essential if you experience an “adrenal crisis”. An adrenal crisis is a life-threatening situation and requires immediate medical treatment. The person needs to be given an emergency injection of hydrocortisone right away. If you are a family member or close friend of a person with Addison’s, you may find it useful to learn how to give this injection in case of emergency. 

It is essential that people with Addison’s take their medication every day, at the right time of day – this is essential for life. They should also receive ongoing medical support, with regular appointments with their endocrinologist to review their condition. As Addison’s disease is a rare condition, sometimes other medical professionals such as GPs or nurses aren’t very familiar with it or with the need for daily steroid medication. Our charity publishes a range of leaflets to provide guidance to these healthcare professionals on what support people with Addison’s will need.

 What is life like for people with Addison’s disease and adrenal insufficiency? 

Although Addison’s is a life-long condition, it can be treated successfully with replacement hormones. People with Addison’s can have a normal life span and lead full and active lives.

Although extra planning is needed, Addison’s and adrenal insufficiency need not be a barrier to living life to the full. However this is not the case for everyone – everybody is different and therefore everyone’s individual response to Addison’s and adrenal insufficiency and the medication is different.

Is Addison’s disease and adrenal insufficiency a disability? 

Yes. This is because Addison’s and adrenal insufficiency is a life-long condition, it can seriously affect a person’s ability to do normal day-to-day activities and is fatal if left untreated.

Modified from the Addison’s Disease Self Help group in the UK for relevance to the USA.