Fludrocortisone
Indications
Fludrocortisone is the only mineralocorticoid available for clinical use. It is structurally cortisol with a fluorine atom at the 9α position, a small change that confers strong resistance to inactivation by 11β-hydroxysteroid dehydrogenase type 2 in mineralocorticoid target tissues. The result is a markedly amplified mineralocorticoid effect — roughly 125–250-fold more potent than hydrocortisone for sodium retention — at doses (0.05–0.4 mg/day) that produce only a small glucocorticoid contribution. It is therefore the standard agent for replacing aldosterone deficiency and for clinical situations that benefit from sustained sodium and water retention.
| Indication | Approved Population | Therapy Type | Status |
|---|---|---|---|
| Primary adrenocortical insufficiency (Addison disease) | Adults & children | Mineralocorticoid replacement (with glucocorticoid) | FDA Approved |
| Salt-losing congenital adrenal hyperplasia | All ages, lifelong | Replacement (with glucocorticoid; +/- salt supplementation in infancy) | FDA Approved |
The label is narrow because fludrocortisone has been in clinical use since the early 1950s and its formal FDA indications were never updated to reflect the broad off-label uses that are now standard practice. In contemporary medicine the great majority of fludrocortisone prescriptions fall outside the formally approved list but are supported by guideline-level evidence.
Neurogenic orthostatic hypotension (high evidence): 0.1–0.4 mg PO once daily, titrated to symptoms and supine BP — recommended as a first-line pharmacologic option after adequate salt and water intake. Often paired with midodrine, droxidopa, or pyridostigmine. Supine hypertension is the chief dose-limiting concern (Fanciulli et al., AAS/EFAS consensus 2018).
Postural orthostatic tachycardia syndrome — POTS (moderate evidence): 0.1–0.2 mg/day; expert-consensus recommendation, especially in the hypovolaemic POTS subtype.
Septic shock with vasopressor dependence (moderate evidence): 50 µg PO/NG once daily for 7 days alongside hydrocortisone 50 mg IV q6h — reduced 90-day mortality in the APROCCHSS trial (Annane 2018 NEJM). The 2021 Surviving Sepsis Campaign guideline suggests low-dose corticosteroids for refractory septic shock, while acknowledging uncertainty about whether fludrocortisone adds benefit beyond hydrocortisone.
Cerebral salt wasting (moderate evidence): 0.1–0.4 mg/day to correct natriuresis and volume depletion; randomised data exist in tuberculous meningitis (Misra 2018 JAMA Neurology).
Hyperkalaemic type IV renal tubular acidosis (limited evidence): 0.1 mg/day in selected patients with hyporeninaemic hypoaldosteronism, including some on calcineurin inhibitors. Often impractical because of fluid retention and hypertension.
Dosing
Fludrocortisone dosing is titrated by clinical scenario, with adequacy judged on blood pressure, postural symptoms, serum potassium, and — in adrenal insufficiency — plasma renin activity. Doses are far smaller than for any glucocorticoid and the only available strength is the 0.1 mg tablet, which can be split or given on alternate days when half-tablet doses are needed.
Adult Dosing by Clinical Scenario
| Clinical Scenario | Starting Dose | Maintenance Dose | Maximum Dose | Notes |
|---|---|---|---|---|
| Primary adrenal insufficiency (Addison disease) | 0.1 mg PO once daily | 0.05–0.2 mg/day | 0.2 mg/day | Always combined with glucocorticoid replacement (hydrocortisone preferred). Do not reduce salt intake Endocrine Society 2016 |
| Secondary adrenal insufficiency | Not routinely indicated | Aldosterone production is preserved in secondary insufficiency (intact RAAS); fludrocortisone is generally unnecessary Hydrocortisone alone is usually sufficient | ||
| Neurogenic orthostatic hypotension | 0.1 mg PO once daily | Titrate by 0.1 mg every 1–2 wk to 0.1–0.3 mg/day | 0.4 mg/day | Combine with high-salt diet (≥10 g/day) and 2–2.5 L fluid intake. Add midodrine, droxidopa, or pyridostigmine for inadequate response Stop and reassess if supine BP >180/100 mmHg |
| Postural orthostatic tachycardia syndrome (POTS) | 0.05–0.1 mg PO once daily | Titrate to 0.1–0.2 mg/day | 0.2 mg/day | Most useful in hypovolaemic phenotype; less effective in hyperadrenergic POTS Expert-consensus recommendation |
| Septic shock (APROCCHSS regimen) | 50 µg PO/NG once daily | 50 µg/day × 7 days, no taper | 50 µg/day | Always given alongside hydrocortisone 50 mg IV q6h Annane 2018 NEJM; absorption may be impaired in critical illness (Polito 2016) |
| Cerebral salt-wasting syndrome | 0.1 mg PO once daily | 0.1–0.4 mg/day | 0.4 mg/day | Studied in tuberculous meningitis (Misra 2018); also used after subarachnoid haemorrhage and TBI Combine with adequate sodium intake |
| Hyperkalaemic type IV RTA / hyporeninaemic hypoaldosteronism | 0.1 mg PO once daily | 0.05–0.2 mg/day if tolerated | 0.2 mg/day | Often limited by fluid retention and hypertension; loop diuretic may be added Patiromer or sodium zirconium are usually preferred |
| Adrenal crisis / acute illness in known adrenal insufficiency | Continue usual fludrocortisone dose; intensify glucocorticoid | High-dose hydrocortisone (≥50 mg q6h IV) provides sufficient mineralocorticoid activity, so no fludrocortisone increase is needed during stress dosing Resume oral fludrocortisone once oral intake returns | ||
Pediatric Dosing
| Clinical Scenario | Starting Dose | Maintenance Dose | Maximum Dose | Notes |
|---|---|---|---|---|
| Salt-losing congenital adrenal hyperplasia (infants) | 0.05–0.2 mg PO daily, often divided BID | 0.05–0.3 mg/day in infancy | 0.3 mg/day | Add sodium chloride 1–2 g/day (~17–34 mEq) for the first 8–12 months Endocrine Society 2018 |
| Salt-losing CAH (older children & adolescents) | 0.05–0.1 mg PO once daily | 0.05–0.2 mg/day | 0.2 mg/day | Salt supplementation is usually not required after weaning Titrate to plasma renin activity in upper-normal range |
| Primary adrenal insufficiency (children) | 0.05–0.1 mg PO once daily | 0.05–0.2 mg/day | 0.2 mg/day | Always combined with hydrocortisone (do not use long-acting glucocorticoids in growing children) Monitor growth, BP, plasma renin |
Adjustment in Special Populations
| Population | Starting Dose | Maintenance Dose | Maximum Dose | Notes |
|---|---|---|---|---|
| Older adults (≥65 y) | 0.05 mg PO once daily | Lowest effective dose, often ≤0.1 mg/day | 0.2 mg/day | Higher risk of supine hypertension, fluid overload, and hypokalaemia. Monitor closely for heart failure Avoid in established heart failure |
| Hypertension or heart failure | Use only if essential | Lowest dose tolerated; add diuretic for oedema | As clinically required | Adrenal insufficiency takes precedence — never withhold replacement Hydrocortisone alone may sometimes suffice in mild cases |
| Hepatic impairment | 0.05 mg PO once daily | Titrate cautiously | As tolerated | Effects may be amplified; monitor BP and electrolytes more frequently |
| Pregnancy | Continue pre-pregnancy dose | Often need to increase by 25–50% in T2/T3 | As required | Progesterone has antimineralocorticoid activity; renin/electrolytes guide adjustment Stress-dose hydrocortisone during labour |
Fludrocortisone cannot retain sodium that is not being eaten. Patients on the drug should not be on a salt-restricted diet — a normal-to-liberal salt intake is essential for the medicine to work. In adrenal insufficiency this is usually achieved by adding salt to food to taste; in orthostatic hypotension a deliberate target of ≥10 g/day (170 mmol Na+) is common. Conversely, an unexplained loss of efficacy on a stable dose is most often the result of new salt restriction, not loss of drug response.
During major stress, hydrocortisone at 100–300 mg/day provides ≈1–3 mg/day of mineralocorticoid effect (hydrocortisone has weak mineralocorticoid activity at high doses). This is more than enough to cover the patient’s mineralocorticoid needs, so fludrocortisone does not need to be increased during stress dosing — the glucocorticoid is doing the work. Resume the usual fludrocortisone dose once oral hydrocortisone returns to a maintenance level (<50 mg/day).
Pharmacology
Mechanism of Action
Fludrocortisone activates the cytoplasmic mineralocorticoid receptor (MR) in epithelial cells of the distal nephron, distal colon, and salivary and sweat ducts. The activated receptor translocates to the nucleus and increases transcription of the epithelial sodium channel (ENaC), the basolateral Na+/K+-ATPase, and serum/glucocorticoid-regulated kinase 1, the net effect of which is reabsorption of sodium and water from tubular fluid in exchange for potassium and hydrogen ions. The resulting expansion of plasma volume raises blood pressure and corrects orthostatic symptoms; the increased K+ excretion accounts for the principal adverse effect. The 9α-fluorine substitution on the cortisol scaffold makes fludrocortisone resistant to inactivation by 11β-hydroxysteroid dehydrogenase type 2, the enzyme that normally protects the mineralocorticoid receptor from cortisol — a single chemical change that effectively converts cortisol into a selective mineralocorticoid.
ADME Profile
| Parameter | Value | Clinical Implication |
|---|---|---|
| Absorption | Rapid and nearly complete oral absorption; Tmax ~0.5–2 h; high-fat meals enhance absorption; antacids may modestly reduce it | Single morning dose adequate in most patients; absorption may be impaired in critical illness or severe enteropathy (Polito 2016) |
| Distribution | Vd ~0.4–0.6 L/kg; protein binding 70–80% (mainly albumin) | Lower Vd than glucocorticoids; effect is concentrated at epithelial mineralocorticoid sites |
| Metabolism | Hepatic, with the active drug derived from hydrolysis of the acetate prodrug; metabolism by hydrolysis, reduction, and oxidation; resistant to 11β-HSD2 inactivation | Strong CYP3A4 inducers (rifampin, phenytoin, carbamazepine) accelerate clearance and may require dose increase; 11β-HSD2 resistance accounts for the disproportionate mineralocorticoid potency |
| Elimination | Plasma t½ ~1–3.5 h; biological t½ 18–36 h; metabolites and small amounts of unchanged drug excreted in urine | Once-daily morning dosing covers the day in most patients; renal impairment does not require dose adjustment |
Comparative potency: fludrocortisone has roughly 10–15× the glucocorticoid potency and 125–250× the mineralocorticoid potency of hydrocortisone. A 0.1 mg dose therefore delivers approximately 1–1.5 mg of hydrocortisone-equivalent glucocorticoid effect — clinically negligible — alongside a substantial mineralocorticoid load. This is why patients with adrenal insufficiency still require a dedicated glucocorticoid replacement (typically hydrocortisone 15–25 mg/day) in addition to fludrocortisone.
Side Effects
The adverse-effect profile of fludrocortisone reflects mineralocorticoid excess: sodium retention, oedema, hypertension, hypokalaemia, and the cardiovascular consequences of these. At typical replacement doses (0.05–0.2 mg/day) most patients tolerate the drug well; problems arise predominantly when dose, salt intake, or co-medications push the patient into volume overload. Glucocorticoid-class adverse effects (osteoporosis, hyperglycaemia, cushingoid features) are uncommon at replacement doses but emerge at 0.4 mg/day and above.
| Adverse Effect | Incidence | Clinical Note |
|---|---|---|
| Mild peripheral oedema | ~10–25% on chronic therapy | Often dose-dependent and self-limiting in the first weeks; persistent oedema requires dose review or addition of a loop diuretic |
| Hypokalaemia | ~10–30% (dose-dependent) | More common at doses ≥0.2 mg/day or with concomitant loop/thiazide diuretics; supplement potassium proactively |
| Hypertension or rise in baseline BP | ~10–15% | Clinically significant elevation usually responds to dose reduction; supine hypertension is the chief concern in orthostatic-hypotension patients |
| Headache | ~10–15% | Often mild and self-limiting; worsening or thunderclap headache should prompt BP measurement |
| Adverse Effect | Incidence | Clinical Note |
|---|---|---|
| Weight gain | ~5–10% | Predominantly fluid retention rather than glucocorticoid-mediated central adiposity at replacement doses |
| Hypomagnesaemia | ~5–10% | Often parallels hypokalaemia; check Mg if K+ is hard to correct |
| Hypernatraemia | ~3–5% | Mild rise of serum Na+ is common; usually does not need intervention |
| Insomnia & mood change | ~3–5% | More likely if dose is given in the evening; switch to morning administration |
| Acne & cushingoid features (chronic high-dose use) | ~1–5% at >0.2 mg/day | Reflects the glucocorticoid component; uncommon at replacement doses |
| Hyperglycaemia (chronic high-dose use) | ~2–5% | Dose-related; check glucose if dose ≥0.3 mg/day or pre-diabetic |
| Adverse Effect | Estimated Frequency | Typical Onset | Required Action |
|---|---|---|---|
| Severe hypertension | ~1–3%; higher in older adults | Within weeks of starting or dose escalation | Reduce or stop dose; treat with calcium channel blocker (avoid thiazide which worsens hypokalaemia); reassess salt intake |
| Decompensated heart failure / pulmonary oedema | Rare at replacement doses; higher in older adults and those with structural heart disease | Days to weeks of overdosing | Stop fludrocortisone; loop diuretic; address underlying cardiac disease; restart at lower dose if essential |
| Severe hypokalaemia (≤2.5 mmol/L) and arrhythmia | ~1% at doses ≥0.2 mg/day | Days to weeks; precipitated by diuretics or vomiting | Urgent potassium replacement (oral or IV); ECG monitoring; review concurrent diuretics |
| Hypertensive encephalopathy or PRES | Very rare | Days–weeks after marked BP elevation | Discontinue, control BP, neuro-imaging |
| Adrenal crisis (after abrupt withdrawal in adrenal insufficiency) | Variable; depends on glucocorticoid status more than fludrocortisone alone | Hours to days after missed doses during illness | Parenteral hydrocortisone 100 mg + IV fluids; resume oral fludrocortisone once stable |
| Glaucoma / posterior subcapsular cataract (long-term use) | Rare at replacement doses; increases with high-dose chronic use | Months–years | Annual ophthalmology review for any patient on chronic glucocorticoid replacement |
| Glucocorticoid-mediated osteoporosis | Uncommon at replacement doses; increases with dose >0.2 mg/day | Months–years | Calcium and vitamin D, weight-bearing exercise; baseline DEXA in chronic high-dose users |
| Anaphylaxis | Very rare | Minutes–hours of administration | Emergency epinephrine; permanent discontinuation; document allergy |
Fludrocortisone is rarely stopped because of intolerance — patients with adrenal insufficiency depend on it lifelong, and most non-replacement uses are time-limited. Withdrawal occurs more often because of dose-limiting hypertension or oedema than because of true intolerance.
| Reason for Discontinuation | Approximate Rate | Context |
|---|---|---|
| Supine hypertension | ~5–10% | Most common limiting factor in orthostatic-hypotension patients |
| Persistent oedema | ~3–5% | Often manageable with loop diuretic + dose reduction |
| Heart failure decompensation | ~1–2% | Mainly in older adults with structural heart disease |
| Refractory hypokalaemia | ~1–2% | Higher with concomitant diuretic or vomiting |
Supine hypertension is the dose-limiting adverse effect in patients treated for neurogenic orthostatic hypotension. Counsel patients to sleep with the head of the bed elevated 30–45° and to avoid taking the dose within 4 hours of lying flat. Check supine BP at clinic visits, not just standing BP — it is common for patients to feel symptomatically improved while running supine BPs >180/100 mmHg, which carries cardiovascular and renal risk over time. A pragmatic ceiling is supine BP ≤160/90 mmHg.
Drug Interactions
The clinically important interactions of fludrocortisone are dominated by pharmacodynamic effects on potassium handling and blood pressure rather than by hepatic enzyme interactions. Co-prescription with diuretics is so common that the patterns below should be anticipated as the rule rather than the exception.
Monitoring
Adequate fludrocortisone replacement is judged by clinical signs (postural symptoms, oedema, weight) and a small panel of laboratory measures. Plasma renin activity is the gold-standard pharmacodynamic marker — a renin in the upper-normal range usually indicates a correctly dosed patient.
-
Blood pressure (supine & standing)
Every visit; weekly during titration
Routine In adrenal insufficiency, target normotension without postural drop >20/10 mmHg. In orthostatic hypotension, target standing BP that prevents symptoms while keeping supine BP ≤160/90 mmHg. -
Serum potassium
Baseline, week 1–2, then every 3–6 months
Routine Target potassium 3.8–5.0 mmol/L. Check more frequently with concurrent diuretic, ACEI/ARB, or NSAID; supplement proactively at doses ≥0.2 mg/day. -
Serum sodium
Baseline, then every 3–6 months
Routine Should be normal-to-high in well-replaced patients. A falling sodium is an early sign of under-replacement, especially during illness or salt restriction. -
Plasma renin activity (PRA) or direct renin concentration
Baseline, then 3–6 months after dose change
Routine Aim for upper-normal range. Markedly elevated renin suggests under-replacement; suppressed renin suggests over-replacement and predisposes to hypertension. Concomitant ACE inhibitor or ARB invalidates renin as a titration marker. -
Body weight & oedema
Every visit; daily home weight after dose change
Routine Rapid weight gain (>2 kg in a week) signals fluid retention and warrants dose review; persistent ankle oedema usually settles with dose reduction or addition of a low-dose loop diuretic. -
Linear growth (children)
Every 3–6 months
Routine Over-replacement (especially of the concomitant glucocorticoid) is a leading cause of growth failure in CAH. Plot height velocity and bone age annually. -
ECG
If unexplained palpitations or potassium <3 mmol/L
Trigger-based Look for U waves, prolonged QT, and arrhythmia in the context of severe hypokalaemia. -
DEXA bone densitometry
Baseline if chronic high-dose use (≥0.2 mg/day) anticipated
Trigger-based Replacement-dose fludrocortisone alone is not a major bone risk; concomitant glucocorticoid usually drives the indication for bone surveillance. -
Ophthalmology review
Annually if chronic high-dose use
Trigger-based Posterior subcapsular cataract and steroid-induced glaucoma reflect the glucocorticoid component; routine review is more relevant for the concurrent hydrocortisone or prednisolone.
Contraindications & Cautions
Absolute Contraindications
- Documented hypersensitivity to fludrocortisone or any excipient.
- Untreated systemic fungal infection. Even at replacement doses, the glucocorticoid component can permit dissemination.
- Live attenuated vaccines in patients receiving combined glucocorticoid replacement that exceeds the ACIP-defined immunosuppressive threshold.
Relative Contraindications (Specialist Input Recommended)
- Uncontrolled hypertension — fludrocortisone will worsen it; if essential for adrenal insufficiency, use the lowest effective dose with intensified antihypertensive therapy.
- Decompensated heart failure — sodium and water retention can precipitate pulmonary oedema; consider whether high-dose hydrocortisone alone could provide enough mineralocorticoid cover.
- Severe hypokalaemia — correct potassium before initiation.
- Active or latent tuberculosis without concurrent antitubercular therapy, when fludrocortisone is being used in combination with high-dose glucocorticoid.
- Severe renal impairment with overt fluid overload — may worsen volume status.
- Concurrent strong potassium-sparing diuretic in adrenal insufficiency — antagonises the desired effect.
Use with Caution
- Older adults — heightened risk of supine hypertension, fluid overload, and electrolyte disturbance.
- Diabetes mellitus — at higher fludrocortisone doses (≥0.2 mg/day) glucocorticoid contribution may worsen glycaemia.
- Pregnancy — replacement doses are compatible; doses often need to be increased in the second and third trimesters because of the antimineralocorticoid effect of progesterone.
- Children — monitor growth velocity; over-replacement is the leading cause of growth failure in CAH.
- Concurrent NSAID, diuretic, or RAAS inhibitor — pharmacodynamic interactions are common; monitor electrolytes more frequently.
- Glaucoma or strong family history — baseline IOP and ophthalmology review.
Fludrocortisone is a corticosteroid and shares the class-wide warning that abrupt withdrawal of corticosteroid therapy after extended use may precipitate adrenal crisis. Patients with adrenal insufficiency depend on fludrocortisone (and the concurrent glucocorticoid) lifelong; missed doses during illness, surgery, or vomiting can cause life-threatening salt wasting, hyponatraemia, hyperkalaemia, and circulatory collapse. All patients should carry a medical-alert card identifying steroid dependence and be educated in sick-day rules: continue fludrocortisone, double the glucocorticoid during minor illness, and seek urgent parenteral hydrocortisone if vomiting prevents oral therapy.
Additional class-level cautions include increased susceptibility to infection (with masking of signs at higher doses), risk of sodium retention and oedema, and risk of hypokalaemia and cardiac arrhythmia.
Patient Counselling
Purpose of Therapy
Explain that fludrocortisone replaces the salt-and-water-balance hormone (aldosterone) that the adrenal glands normally make, or — when used for orthostatic hypotension or POTS — boosts the body’s ability to retain salt and water in order to keep blood pressure up when standing. Set expectations: patients with adrenal insufficiency need this medicine for life, alongside their glucocorticoid (usually hydrocortisone). Patients using it for orthostatic problems may take it short-term or long-term depending on response.
How to Take
Take the dose once daily in the morning with or without food. If a dose is missed and remembered the same day, take it as soon as possible; if it is already evening, skip and resume the next morning rather than doubling up. Never stop the medicine suddenly without speaking to the prescriber, especially if it is being taken for adrenal insufficiency — abrupt stopping can cause a dangerous drop in blood pressure and salt levels. Tablets can be split if a half dose is needed.
Sources
- U.S. Food and Drug Administration / DailyMed. Fludrocortisone acetate (Florinef) tablets — current full prescribing information. https://dailymed.nlm.nih.gov/dailymed/search.cfm?query=fludrocortisone Authoritative source for FDA-approved indications (primary adrenocortical insufficiency, salt-losing CAH), dosing, contraindications, and adverse-reaction tables.
- Electronic Medicines Compendium (eMC). Fludrocortisone acetate — Summary of Product Characteristics. https://www.medicines.org.uk/emc/search?q=fludrocortisone UK regulatory equivalent of the FDA label, including paediatric dosing detail.
- World Health Organization. Model List of Essential Medicines — fludrocortisone. https://list.essentialmeds.org/ WHO designation of fludrocortisone as an essential medicine for adrenal insufficiency.
- Annane D, Renault A, Brun-Buisson C, et al; CRICS-TRIGGERSEP Network. Hydrocortisone plus fludrocortisone for adults with septic shock (APROCCHSS). N Engl J Med. 2018;378(9):809–818. doi:10.1056/NEJMoa1705716. PMID 29490185. https://pubmed.ncbi.nlm.nih.gov/29490185/ Pivotal RCT showing reduced 90-day mortality with hydrocortisone 50 mg q6h plus fludrocortisone 50 µg/day for 7 days in septic shock.
- Annane D, Sébille V, Charpentier C, et al. Effect of treatment with low doses of hydrocortisone and fludrocortisone on mortality in patients with septic shock. JAMA. 2002;288(7):862–871. doi:10.1001/jama.288.7.862. PMID 12186604. https://pubmed.ncbi.nlm.nih.gov/12186604/ Original 2002 trial that introduced the hydrocortisone–fludrocortisone combination to critical-care practice.
- Misra UK, Kalita J, Kumar M. Safety and efficacy of fludrocortisone in the treatment of cerebral salt wasting in patients with tuberculous meningitis: a randomized clinical trial. JAMA Neurol. 2018;75(11):1383–1391. doi:10.1001/jamaneurol.2018.2178. PMID 30105362. https://pubmed.ncbi.nlm.nih.gov/30105362/ RCT demonstrating that fludrocortisone normalised serum sodium and natriuresis more rapidly than saline alone in tuberculous meningitis-associated cerebral salt wasting.
- Bosch NA, Teja B, Law AC, Pang B, Jafarzadeh SR, Walkey AJ. Comparative effectiveness of fludrocortisone and hydrocortisone vs hydrocortisone alone among patients with septic shock. JAMA Intern Med. 2023;183(5):451–459. doi:10.1001/jamainternmed.2023.0258. PMID 36972033. https://pubmed.ncbi.nlm.nih.gov/36972033/ Large target-trial-emulation cohort study supporting incremental benefit of adding fludrocortisone to hydrocortisone in septic shock.
- Ekman B, Quinkler M, Zhang P, Isidori AM, Murray RD, Wahlberg J. Mineralocorticoid effects of fludrocortisone and hydrocortisone in primary adrenal insufficiency: EU-AIR patient data. J Endocrinol Invest. 2025. doi:10.1007/s40618-025-02657-7. PMID 40913682. https://pubmed.ncbi.nlm.nih.gov/40913682/ European Adrenal Insufficiency Registry analysis quantifying combined mineralocorticoid potency of typical fludrocortisone + hydrocortisone replacement combinations.
- Bornstein SR, Allolio B, Arlt W, et al. Diagnosis and treatment of primary adrenal insufficiency: an Endocrine Society clinical practice guideline. J Clin Endocrinol Metab. 2016;101(2):364–389. doi:10.1210/jc.2015-1710. PMID 26760044. https://pubmed.ncbi.nlm.nih.gov/26760044/ Definitive guideline for replacement strategy in primary adrenal insufficiency, including target dose, monitoring, and pregnancy adjustment.
- Speiser PW, Arlt W, Auchus RJ, et al. Congenital adrenal hyperplasia due to steroid 21-hydroxylase deficiency: an Endocrine Society clinical practice guideline. J Clin Endocrinol Metab. 2018;103(11):4043–4088. doi:10.1210/jc.2018-01865. PMID 30272171. https://pubmed.ncbi.nlm.nih.gov/30272171/ Anchor reference for fludrocortisone dosing and monitoring across the paediatric and adult salt-losing CAH lifespan, including the role of supplementary sodium chloride in infancy.
- Fanciulli A, Jordan J, Biaggioni I, et al. Consensus statement on the definition of neurogenic supine hypertension in cardiovascular autonomic failure by the American Autonomic Society (AAS) and the European Federation of Autonomic Societies (EFAS). Clin Auton Res. 2018;28(4):355–362. doi:10.1007/s10286-018-0529-8. PMID 29766366. https://pubmed.ncbi.nlm.nih.gov/29766366/ Multi-society consensus on the diagnosis and management of supine hypertension that complicates fludrocortisone therapy in neurogenic orthostatic hypotension.
- Arnold AC, Ng J, Raj SR. Postural tachycardia syndrome — diagnosis, physiology, and prognosis. Auton Neurosci. 2018;215:3–11. doi:10.1016/j.autneu.2018.02.005. PMID 29523389. https://pubmed.ncbi.nlm.nih.gov/29523389/ Clinical overview supporting fludrocortisone as a pharmacologic option in selected POTS phenotypes, particularly the hypovolaemic subtype.
- Evans L, Rhodes A, Alhazzani W, et al. Surviving Sepsis Campaign: international guidelines for management of sepsis and septic shock 2021. Crit Care Med. 2021;49(11):e1063–e1143. doi:10.1097/CCM.0000000000005337. PMID 34605781. https://pubmed.ncbi.nlm.nih.gov/34605781/ Surviving Sepsis recommendations on low-dose corticosteroid therapy in vasopressor-dependent septic shock.
- Centers for Disease Control and Prevention. ACIP General Best Practice Guidelines for Immunization — altered immunocompetence. https://www.cdc.gov/vaccines/hcp/acip-recs/general-recs/immunocompetence.html Defines the dose and duration thresholds for clinically significant glucocorticoid-induced immunosuppression and live-vaccine avoidance.
- Cain DW, Cidlowski JA. Immune regulation by glucocorticoids. Nat Rev Immunol. 2017;17(4):233–247. doi:10.1038/nri.2017.1. PMID 28192415. https://pubmed.ncbi.nlm.nih.gov/28192415/ Review of glucocorticoid effects on innate and adaptive immunity, applicable to the smaller glucocorticoid component of fludrocortisone.
- Polito A, Hamitouche N, Ribot M, et al. Pharmacokinetics of oral fludrocortisone in septic shock. Br J Clin Pharmacol. 2016;82(6):1509–1516. doi:10.1111/bcp.13065. PMID 27411519. https://pubmed.ncbi.nlm.nih.gov/27411519/ Verified PK study of enteral fludrocortisone in critically ill patients; reports detectable plasma concentrations with terminal half-life ~2.5–3.5 h and underpins the variable-absorption observation in septic shock.
- U.S. National Library of Medicine. LactMed — Fludrocortisone. https://www.ncbi.nlm.nih.gov/books/NBK500960/ Lactation-safety reference confirming compatibility of replacement-dose fludrocortisone with breastfeeding.