Fludrocortisone | Mineralocorticoid | CAS 127-31-1

Product Name: Fludrocortisone
CAS No.: 127-31-1
Chemical Name: (11β)-9-fluoro-11,17,21-trihydroxypregn-4-ene-3,20-dione
Molecular Formula: C₂₁H₂₉FO₅
Appearance: White or almost white crystalline powder
Solubility: Practically insoluble in water; moderately soluble in ethanol; sparingly soluble in ether. Often used as acetate for oral administration.
Stability: Relatively stable when stored protected from light

1. Introduction

Fludrocortisone is a synthetic steroid hormone with very high mineralocorticoid and moderate glucocorticoid activity. It is used for replacement therapy in adrenal insufficiency (Addison's disease) to correct electrolyte balance and blood pressure.

Mineralocorticoids, the main representative of which in the human body is aldosterone, play a critical role in the regulation of water-electrolyte balance and maintenance of blood pressure. In adrenal insufficiency, the synthesis of these hormones is reduced, leading to life-threatening conditions. Fludrocortisone, possessing potent mineralocorticoid activity, is used to replace this deficiency.

2. Chemical Structure & Synthesis

Fludrocortisone is a fluorinated derivative of hydrocortisone (cortisol). The introduction of a fluorine atom at the 9α-position of the steroid structure significantly enhances mineralocorticoid activity and, to some extent, glucocorticoid activity.

Synthesis: Fludrocortisone is obtained by chemical modification of natural steroids or their synthetic analogs. Key steps include the introduction of a fluorine atom at the 9α-position and hydroxylation at positions 11, 17, and 21.

3. Mechanism of Action

Fludrocortisone binds to mineralocorticoid receptors in the distal renal tubules and other tissues. This leads to increased reabsorption of sodium and water, as well as increased excretion of potassium and hydrogen ions. As a result, circulating blood volume and blood pressure increase. It also has glucocorticoid effects (anti-inflammatory, immunosuppressive), but due to its high mineralocorticoid activity, these effects are usually less pronounced at therapeutic doses.

4. Pharmacokinetics

Well absorbed from the gastrointestinal tract. Binds to plasma proteins (transcortin and albumin). Metabolized in the liver and excreted by the kidneys.

5. Applications

• Replacement therapy for primary chronic adrenal insufficiency (Addison's disease)

• Replacement therapy for secondary chronic adrenal insufficiency (ACTH deficiency)

• Salt-losing forms of congenital adrenal hyperplasia (adrenogenital syndrome)

• Idiopathic orthostatic hypotension (to increase blood pressure)

6. Conclusion

Fludrocortisone is a life-saving drug for patients with adrenal insufficiency, effectively correcting water-electrolyte imbalances and maintaining stable blood pressure. Its use requires careful dose selection and regular monitoring of electrolytes and blood pressure due to its potent mineralocorticoid action and the risk of side effects associated with fluid retention and hypokalemia.