氟氢可的松 (Florinef)

概览

Fludrocortisone is a mineralocorticoid used to treat adrenocortical insufficiency and salt-losing adrenogenital syndrome.

作用机制

The main endogenous mineralocorticoid, aldosterone, is produced in the zona glomerulosa of the adrenal cortex - it acts on mineralocorticoid receptors in the kidneys to increase sodium reabsorption and potassium excretion, which in turn helps to regulate plasma electrolyte composition and blood pressure. In conditions of adrenal insufficiency, such as Addison’s disease, aldosterone is not produced (or is produced in insufficient quantities) and must be replaced by exogenous mineralocorticoids such as fludrocortisone. Fludrocortisone binding to mineralocorticoid receptors causes alterations to DNA transcription and translation of proteins that result in an increased density of sodium channels on the apical side of renal tubule cells and an increased density of Na-K-ATPase on the basolateral side. These increases in receptor density result in increased plasma sodium concentrations, and thus increased blood pressure, as well as a decreased plasma potassium concentration. Fludrocortisone may also exert a direct effect on plasma sodium levels via action at the Na-H exchanger found in the apical membrane of renal tubule cells. Fludrocortisone also acts on glucocorticoid receptors, albeit with a much lower affinity - the glucocorticoid potency of fludrocortisone is approximately 5-10 times that of endogenous cortisol, whereas its mineralocorticoid potency is 200-400 times greater.

适应症

Fludrocortisone is indicated as partial replacement therapy for primary or secondary adrenocortical insufficiency in Addison's disease. It is also indicated for the treatment of salt-losing androgenital syndrome.

• Otitis Externa
• Otitis Media (OM)
• Primary adrenocortical insufficiency
• Secondary adrenocortical insufficiency
• Salt-losing Androgenital syndrome