What is the recommended starting dose of fludrocortisone for treating orthostatic hypotension?

Fludrocortisone Dosing for Orthostatic Hypotension

Start fludrocortisone at 0.05-0.1 mg once daily and titrate to 0.1-0.3 mg daily based on symptom response, blood pressure control, and adverse effects. 1

Initial Dosing Strategy

The recommended starting dose is 0.05-0.1 mg daily, taken as a single morning dose 1. Some guidelines suggest an alternative approach with a 0.2 mg loading dose followed by 0.1 mg daily maintenance 2, though the lower starting dose of 0.05-0.1 mg is more widely endorsed and allows for better tolerability assessment 1.

Titration and Maximum Dose

• Titrate individually to a typical maintenance range of 0.1-0.3 mg daily based on symptom improvement, standing blood pressure response, and development of adverse effects 1
• The maximum recommended dose is 1.0 mg daily 2, though doses above 0.3 mg daily carry increased risk of serious adverse effects including adrenal suppression and immunosuppression 2
• Most patients achieve adequate symptom control within the 0.1-0.3 mg daily range without requiring higher doses 1

Mechanism and Expected Effects

Fludrocortisone works through sodium retention and direct vessel wall effects to increase plasma volume 1. The medication expands body fluid volume, which appears to be allocated more to the perivascular space than intravascular space, ultimately limiting the orthostatic decrease in cardiac output 3. Clinical improvement typically manifests as reduced orthostatic blood pressure drop and improved standing tolerance 4, 3.

When to Use Fludrocortisone

Fludrocortisone should be considered as first-line pharmacological therapy after non-pharmacological measures (increased fluid/salt intake, compression garments, physical counter-maneuvers) have proven insufficient 2, 1. However, avoid fludrocortisone when supine hypertension is already present—use other medications first in this scenario 2.

Critical Monitoring Requirements

• Supine hypertension: The most important limiting factor; monitor blood pressure in both standing and supine positions regularly 2, 1
• Hypokalemia: Check electrolytes periodically as mineralocorticoid effects can cause potassium wasting 2
• Edema and weight gain: Monitor for peripheral edema and track body weight (expect 1-2 kg increase with treatment) 2, 4
• Heart failure exacerbation: Fludrocortisone is poorly tolerated in patients with heart failure due to volume expansion 2, 1

Contraindications and Precautions

Do not use fludrocortisone in patients with:

• Active heart failure or significant cardiac dysfunction 2, 1
• Pre-existing supine hypertension (use alternative agents first) 2
• Severe renal disease where sodium retention would be harmful 1

Combination Therapy

For patients who do not respond adequately to fludrocortisone monotherapy, consider adding midodrine (starting at 2.5-5 mg three times daily) 1. This combination approach targets both volume expansion (fludrocortisone) and peripheral vasoconstriction (midodrine), providing complementary mechanisms of action 2, 1.

Adjunctive Non-Pharmacological Measures

Even when using fludrocortisone, continue emphasizing:

• Increased salt intake to 6-9 g daily (if not contraindicated by heart failure) 2, 1
• Fluid intake of 2-3 liters daily 1
• Head-up bed elevation by 10 degrees during sleep to prevent nocturnal polyuria and reduce supine hypertension risk 1, 4
• Compression garments (thigh-high or abdominal) to reduce venous pooling 2, 1

Treatment Goals

The therapeutic objective is minimizing postural symptoms rather than restoring normotension 2, 1. Accept some degree of orthostatic blood pressure drop if the patient remains asymptomatic and functional. Balance the benefits of increasing standing blood pressure against the risk of inducing supine hypertension, which can cause end-organ damage 1.

Evidence Quality Considerations

While fludrocortisone is widely recommended as first-line therapy in multiple guidelines 2, 1, the actual RCT evidence is limited—a 2021 Cochrane review found only very low-certainty evidence from small, short-term trials 5. Despite this, decades of clinical experience and consistent guideline recommendations support its use, particularly when combined with non-pharmacological measures 4, 3, 6.