Adrenal insufficiency

What it is

Adrenal insufficiency means the body cannot make enough cortisol. In primary disease (Addison’s disease) the adrenal glands themselves are damaged, usually by autoimmunity, and aldosterone is lost too. In secondary disease the pituitary stops sending ACTH. The most common form is glucocorticoid-induced: steroid medicines taken for weeks to months switch off the body’s own production, which can be slow to recover.

Symptoms

• Persistent fatigue and weakness

• Weight loss, poor appetite, nausea

• Dizziness on standing and low blood pressure

• Salt craving and darkening of the skin and gums in primary disease

• Vomiting, severe weakness and confusion in an adrenal crisis

How it affects the whole body

• Brain and cognition: Poor concentration and low mood are common and improve with replacement.

• Sexual health: The adrenal glands are the main source of androgens in women, so desire can fall.

• Muscle: Weakness and muscle aches are typical.

• Bone: The disease itself does not thin bone. Excess replacement doses do, so the lowest effective dose is used.

• Energy: Fatigue is the dominant symptom and often persists to some degree despite treatment.

How it’s diagnosed

An early-morning cortisol with ACTH, followed by a cosyntropin (ACTH) stimulation test when the result is uncertain. Saliva panels are not used for diagnosis.

Treatment and clinical benefits

Hydrocortisone in two or three daily doses, or prednisone, replaces cortisol. Fludrocortisone replaces aldosterone in primary disease. Treatment restores energy, appetite and blood pressure and is lifesaving. The Endocrine Society suggests a trial of DHEA for women with low libido, low mood or low energy despite otherwise good replacement.

Vitality and longevity

With correct replacement and sick-day rules, life expectancy approaches normal. The risks come from the two extremes: adrenal crisis from too little cortisol during illness, and bone loss, weight gain and diabetes from too much.

Clinical pearls

• Sick-day rules: double or triple the dose during fever or illness, and use injectable hydrocortisone if vomiting.

• Carry a steroid alert card or bracelet.

• Never stop long-term steroid medicines suddenly. A 2024 joint European and US guideline covers how to taper and when to test.