Optimal Timing for Fludrocortisone Administration
Fludrocortisone should be taken as a single dose upon awakening each morning. 1
Standard Administration Protocol
Take fludrocortisone once daily in the morning immediately upon awakening, typically at a dose ranging from 50-200 µg for most patients with primary adrenal insufficiency. 1
The morning timing is essential because it aligns with the body's natural circadian rhythm of mineralocorticoid activity and ensures consistent blood pressure regulation and electrolyte homeostasis throughout the day. 1
Daily dosing (not alternate-day) is mandatory because the medication's pharmacokinetics do not support skipping days, and mineralocorticoids are vital for maintaining blood pressure and preventing life-threatening adrenal crises. 1
Why Morning Dosing Matters
Taking fludrocortisone upon awakening provides optimal coverage during waking hours when orthostatic stress and physical activity are highest, requiring maximal mineralocorticoid support for blood pressure maintenance. 1
The medication works continuously throughout the day to maintain sodium retention and potassium excretion; morning administration ensures peak effect during periods of greatest physiological demand. 1
Coordination with Glucocorticoid Therapy
When taking both fludrocortisone and glucocorticoid replacement (such as prednisolone or hydrocortisone), both medications should be taken together in the morning upon awakening for simplicity and compliance. 2
All patients with primary adrenal insufficiency require fludrocortisone 0.05-0.2 mg daily in addition to their glucocorticoid replacement. 2
Critical Pitfalls to Avoid
Never attempt alternate-day dosing to manage side effects like mild edema or blood pressure elevation—this creates dangerous gaps in mineralocorticoid coverage and dramatically increases adrenal crisis risk. 1
Do not take fludrocortisone at bedtime, as this timing provides no physiological advantage and may contribute to nocturnal hypertension or edema. 1
Irregular dosing or skipping days can trigger adrenal crisis characterized by hypotension, hyponatremia, hyperkalemia, and potentially life-threatening cardiovascular collapse. 1
Under-replacement with fludrocortisone is common and predisposes patients to recurrent adrenal crises—do not compensate for inadequate mineralocorticoid dosing by increasing glucocorticoids, as this leads to glucocorticoid excess while maintaining crisis risk. 2
Monitoring for Proper Dosing
Assess blood pressure in both supine and standing positions: orthostatic hypotension or persistent salt cravings suggest under-replacement requiring dose increase, while hypertension or peripheral edema suggest over-replacement requiring dose reduction (but never complete discontinuation). 1, 3
Monitor serum electrolytes regularly—low sodium or high potassium warrant dose increases. 1