Overview
Hydrocortisone is a short-acting corticosteroid that is chemically identical to cortisol, the natural stress hormone produced by the adrenal glands. It possesses both glucocorticoid and mineralocorticoid properties and is essential for replacement therapy in adrenal insufficiency.

Mechanism of Action
It binds to both glucocorticoid and mineralocorticoid receptors. Its glucocorticoid activity reduces inflammation and modulates metabolism, while its mineralocorticoid activity promotes sodium retention and potassium excretion in the kidneys, helping to maintain blood pressure and fluid balance.

Dosage and Administration
For adrenal replacement therapy, oral doses typically range from 15 to 30 mg daily, divided into two or three doses to mimic the natural diurnal rhythm of cortisol secretion. During periods of physical stress or illness, the dose must be significantly increased to prevent adrenal crisis.

Side Effects
When used at physiological replacement doses, side effects are rare. However, supraphysiological doses or prolonged use can cause weight gain, fluid retention, hypertension, hyperglycemia, osteoporosis, and increased susceptibility to infections.

Contraindications
Systemic use is contraindicated in patients with systemic fungal infections. It should be used with caution in patients with heart failure, hypertension, peptic ulcers, and active infections, as it can exacerbate these conditions.

Pregnancy and Lactation
It is safe and necessary for adrenal replacement therapy during pregnancy. The placenta naturally metabolizes most of the hydrocortisone before it reaches the fetus. It is considered safe during breastfeeding at standard replacement doses.