How to manage orthostatic hypotension?

Management of Orthostatic Hypotension

Begin with non-pharmacologic interventions including increased fluid and salt intake, compression garments (at least thigh-high, preferably abdominal), physical counter-pressure maneuvers, and acute water ingestion (≥480 mL for maximum effect); if symptoms persist despite these measures, initiate midodrine as first-line pharmacologic therapy, with droxidopa or fludrocortisone as alternatives, while carefully monitoring for supine hypertension. 1

Initial Assessment and Reversible Causes

• Measure orthostatic vital signs properly: After 5 minutes supine rest, measure blood pressure at 1 and 3 minutes after standing, maintaining the arm at heart level throughout 2, 3
• Orthostatic hypotension is confirmed when systolic BP drops ≥20 mmHg or diastolic BP drops ≥10 mmHg within 3 minutes of standing 1, 3
• Review and reduce or eliminate causative medications including diuretics, vasodilators, antihypertensives, alpha-blockers, and beta-blockers where clinically appropriate 1, 2
• Assess for volume depletion and correct dehydration or blood loss as primary interventions 1

Critical Distinction: Neurogenic vs Non-Neurogenic

• Neurogenic orthostatic hypotension results from autonomic failure (Parkinson's disease, multiple system atrophy, pure autonomic failure, diabetic neuropathy) and requires more aggressive pharmacologic management 1
• Non-neurogenic causes (medications, dehydration) often respond to reversible cause correction alone 1

Non-Pharmacologic Interventions (First-Line for All Patients)

Immediate Symptomatic Relief Strategies

• Acute water ingestion: Drink ≥480 mL of water for temporary relief; peak effect occurs at 30 minutes and provides greater benefit than smaller volumes 1

  • Avoid adding glucose or salt to water as this reduces the osmopressor response 1
  • This is for occasional use during periods of increased orthostatic stress, not routine daily management 1

• Physical counter-pressure maneuvers: Leg crossing, lower body muscle tensing, squatting, or maximal handgrip increase blood pressure acutely 1

  • Squatting produces the largest blood pressure increase 1
  • These require sufficient prodromal warning symptoms and physical ability to perform safely 1

Sustained Management Strategies

• Compression garments: Use at least thigh-high stockings, preferably including abdominal compression 1

  • Shorter garments (below thigh) have not proven beneficial 1
  • These improve orthostatic symptoms and blunt blood pressure decreases in elderly patients and those with neurogenic causes 1

• Increase salt and fluid intake: Reasonable in selected patients with neurogenic orthostatic hypotension, though data are limited 1

• Elevate head of bed 30-45 degrees during sleep to reduce supine hypertension and improve morning orthostatic tolerance 4, 5

Pharmacologic Management

First-Line: Midodrine

• Midodrine is FDA-approved for symptomatic orthostatic hypotension and should be used when non-pharmacologic measures fail 6
• Dosing: Start 2.5-10 mg three times daily; increases standing systolic BP by 15-30 mmHg at 1 hour, with effects persisting 2-3 hours 6
• Timing: Give last dose 3-4 hours before bedtime to minimize supine hypertension 6
• Mechanism: Alpha-1 agonist that increases vascular tone without stimulating cardiac beta-receptors or crossing blood-brain barrier 6
• Monitoring: Check supine and standing BP regularly; discontinue if supine hypertension persists 6
• Common side effects: Scalp tingling, piloerection, urinary retention, supine hypertension 1, 6
• Caution with renal impairment: Start at 2.5 mg dose as desglymidodrine is renally eliminated 6

Second-Line: Droxidopa

• Droxidopa is FDA-approved for neurogenic orthostatic hypotension in Parkinson's disease, pure autonomic failure, and multiple system atrophy 1, 2
• Benefits: Improves symptoms and may reduce falls in small studies 1
• Limitations: Carbidopa (used in Parkinson's treatment) may decrease droxidopa effectiveness 1
• Side effects: Supine hypertension, headache, dizziness, nausea limit use and titration 1

Third-Line: Fludrocortisone

• Use fludrocortisone only after other medications when supine hypertension is not present 1
• Mechanism: Increases plasma volume through mineralocorticoid effects 1
• Dosing: Keep doses ≤0.3 mg daily to avoid serious adverse effects 1
• Side effects: Edema, hypokalemia, headache are common; adrenal suppression and immunosuppression occur with higher doses 1
• Contraindication: Do not use when supine hypertension is already present 1

Special Considerations in Elderly and Hypertensive Patients

Critical Evidence on Intensive BP Control

• Asymptomatic orthostatic hypotension should NOT trigger automatic down-titration of antihypertensive therapy, even with lower BP goals 1
• Intensive BP lowering actually reduces orthostatic hypotension risk through improved baroreflex function, reduced left ventricular hypertrophy, and decreased arterial stiffness 1
• In SPRINT trial analysis, orthostatic hypotension was more common in standard (not intensive) treatment groups and was not associated with higher rates of syncope, falls, or cardiovascular events 1

Medication Selection in Frail Elderly

• For patients ≥85 years or with moderate-to-severe frailty: Use long-acting dihydropyridine calcium channel blockers or RAS inhibitors as first-line antihypertensives, followed by low-dose diuretics if needed 2
• Avoid beta-blockers and alpha-blockers in frail elderly unless specifically indicated 2
• Switch (don't just reduce) BP medications that worsen orthostatic hypotension to alternative therapies 2

Common Pitfalls to Avoid

• Do not measure orthostatic vitals only at 3 minutes: Measure at both 1 and 3 minutes as some patients have early drops that normalize by 3 minutes 3
• Do not use glucose or salt-containing beverages for acute water bolus therapy as this reduces effectiveness 1
• Do not prescribe compression stockings that end below the thigh: They are ineffective 1
• Do not automatically reduce antihypertensive medications in patients with asymptomatic orthostatic hypotension, as this may worsen cardiovascular outcomes 1
• Do not combine multiple vasoconstrictive agents (midodrine with phenylephrine, pseudoephedrine, ephedrine) without careful BP monitoring 6
• Do not use MAO inhibitors or linezolid with midodrine 6

Treatment Algorithm

1. Confirm diagnosis with proper orthostatic vital sign measurement (5 minutes supine, then 1 and 3 minutes standing) 2, 3
2. Identify and correct reversible causes: Reduce/eliminate causative medications, correct volume depletion 1
3. Implement non-pharmacologic measures in all patients: compression garments, increased salt/fluid, head-up sleeping, physical maneuvers 1
4. If symptoms persist, start midodrine 2.5-10 mg three times daily (last dose 3-4 hours before bed) 1, 6
5. If midodrine fails or is contraindicated, try droxidopa (especially in neurogenic causes) 1, 2
6. Consider fludrocortisone only if no supine hypertension and other agents have failed 1
7. Monitor supine and standing BP regularly; adjust therapy to minimize symptoms while avoiding excessive supine hypertension 1, 2