Q: What is an "escape phenomenon" of Fludrocortisone?
Answer: Fludrocortisone is a synthetic mineralocorticoid that works by increasing renal sodium and water reabsorption. The overall effect is intravascular volume expansion and increases blood pressure. In prolong use over few weeks, patients develop an "escape phenomenon", which means that overall blood volume hemostasis (balance) goes back to pre-treatment level between intra and extravascular compartments - but its pressor effect stays as it is. This is due to increased peripheral vascular resistance.
Chobanian AV, Volicer L, Tifft CP, et al. Mineralocorticoid-induced hypertension in patients with orthostatic hypotension. N Engl J Med 1979; 301:68.