What is Addison’s disease?
Addison’s disease, also known as primary adrenal insufficiency, is a rare disorder in which the adrenal cortex (outer layer of the adrenal glands) is damaged and cannot produce sufficient cortisol and aldosterone. Cortisol helps the body respond to stress, maintain blood pressure, support immune function, and regulate blood sugar. Aldosterone controls sodium and potassium balance, influencing fluid volume and blood pressure.
Secondary adrenal insufficiency occurs when the pituitary gland fails to secrete enough adrenocorticotropic hormone (ACTH), leading to inadequate cortisol production while aldosterone remains relatively normal.
Untreated Addison’s disease may progress to an adrenal crisis, marked by severe abdominal or back pain, persistent vomiting and diarrhea, dehydration, dangerously low blood pressure, and loss of consciousness.
Causes
- Autoimmune adrenalitis – immune attack on adrenal cortex (most common in developed countries)
- Infections – for example, tuberculosis, HIV/AIDS, fungal or bacterial infections
- Cancer – primary adrenal tumors or metastases from other sites
- Genetic defects – rare inherited enzyme mutations affecting adrenal function
- Medications – long-term corticosteroid therapy or abrupt withdrawal of steroids
- Hemorrhage – bleeding into adrenal glands due to trauma or surgery
- Other endocrine autoimmunity – conditions such as type 1 diabetes or autoimmune thyroid disease
Symptoms
- Chronic fatigue and muscle weakness
- Unintentional weight loss and decreased appetite
- Low blood pressure, dizziness or fainting
- Salt cravings
- Nausea, vomiting, diarrhea
- Darkened skin patches (hyperpigmentation)
- Mood changes – irritability, depression
- Muscle or joint pain
- Hair thinning or loss
- Irregular menstrual periods in women
Symptoms often worsen during physical or emotional stress, illness, injury, or surgery.
Diagnosis
- Medical history and physical exam – look for hyperpigmentation, low blood pressure
- Blood tests – cortisol (low) and ACTH (high) levels, electrolyte panel (sodium, potassium)
- ACTH stimulation test – measures cortisol response to synthetic ACTH
- Imaging – CT or MRI of adrenal glands to detect damage, infection, or tumors
- Autoantibody tests – anti-21-hydroxylase antibodies in autoimmune cases
Treatment
- Glucocorticoid replacement – hydrocortisone, prednisone, or dexamethasone in divided daily doses
- Mineralocorticoid replacement – fludrocortisone to maintain sodium balance and blood pressure
- Dose adjustments – during illness, surgery, or stress to prevent adrenal crisis
- Lifestyle – balanced diet, regular exercise, stress management
- Medical alert identification – informs providers of adrenal insufficiency in emergencies
- Patient education – recognizing adrenal crisis and self-administration of emergency injectable steroids
Complications
- Adrenal crisis – life-threatening emergency requiring immediate steroid and fluid replacement
- Hypoglycemia – low blood sugar due to cortisol deficiency
- Electrolyte disturbances – hyponatremia (low sodium), hyperkalemia (high potassium)
- Dehydration – from aldosterone deficiency and salt loss
- Osteoporosis – long-term glucocorticoid use
- Mood disorders – depression or anxiety related to chronic illness
- Reduced quality of life – fatigue, frequent medical visits, dosage adjustments