Which symptoms are commonly associated with Addison's disease?

The symptoms associated with Addison's disease, particularly hyperpigmentation and fatigue, arise due to the adrenal glands producing insufficient amounts of cortisol and aldosterone.

Hyperpigmentation occurs because of increased levels of adrenocorticotropic hormone (ACTH) in the body, which is stimulated when cortisol levels are low. Elevated ACTH can stimulate melanocyte activity, leading to darkening of the skin, especially in areas subjected to friction, such as elbows and knees.

Fatigue is another hallmark symptom, linked to the overall hormonal imbalance and inadequate secretion of cortisol, which is vital for energy metabolism and stress response. Patients with Addison's disease often find themselves easily fatigued due to insufficient energy production and can experience weakness as a result of low blood pressure and electrolyte imbalances.

The other options presented do not align with the typical symptoms of Addison's disease. For example, weight gain and muscle cramps are more common in conditions where there is an overproduction of hormones or abnormalities in calcium metabolism, rather than the underproduction seen in Addison's. Increased appetite and energy do not reflect the clinical picture of Addison's disease, where patients usually experience decreased appetite and overall low energy levels. Hyperglycemia and hypertension are typically associated with conditions like Cushing's syndrome or