What are the treatment options for orthostatic hypotension?

Treatment Options for Orthostatic Hypotension

The first-line treatment for orthostatic hypotension should include non-pharmacological interventions such as increasing salt intake to 10g daily, increasing fluid intake to 2-3 liters per day, and using physical counter-pressure maneuvers, followed by pharmacological options like midodrine (5-20mg three times daily) or fludrocortisone (0.1-0.3mg once daily) for patients with persistent symptoms. 1

Diagnostic Criteria

• Orthostatic hypotension is defined as a drop in systolic BP ≥20 mmHg or diastolic BP ≥10 mmHg within 3 minutes of standing 1
• Diagnosis requires measuring BP in both supine and standing positions 1
• Consider 24-hour ambulatory BP monitoring to confirm diurnal patterns 1

Treatment Algorithm

Step 1: Non-Pharmacological Interventions

• Increase salt intake to 10g NaCl daily 1
• Increase fluid intake to 2-3 liters per day 1
• Acute water ingestion (480 mL) for immediate temporary relief 1
• Physical counter-pressure maneuvers (leg crossing, squatting, muscle tensing) 1
• Compression garments (thigh-high compression stockings and abdominal binders) 1
• Elevate head of bed by 10° during sleep 1
• Eat small, frequent meals with reduced carbohydrate content 1
• Regular exercise, especially swimming and leg/abdominal muscle exercises 1

Step 2: Medication Review

• Review and adjust/discontinue medications that may contribute to hypotension:
  • Diuretics
  • Vasodilators
  • Alpha-blockers
  • Antipsychotics
  • Beta-blockers 1
  • Over-the-counter cold remedies and diet aids 2

Step 3: Pharmacological Interventions

1. First-line medications:

   • Midodrine (5-20 mg three times daily) 1, 2
     • Take last dose 3-4 hours before bedtime to minimize nighttime supine hypertension 2
     • Starting dose of 2.5 mg for patients with renal impairment 2
   • Fludrocortisone (0.1-0.3 mg once daily) 1

2. Second-line medications:

   • Droxidopa for neurogenic orthostatic hypotension 1

3. Third-line medications:

   • Pyridostigmine (30 mg 2-3 times daily) for refractory cases 1
   • Desmopressin for nocturnal polyuria 1
   • Erythropoietin for patients with anemia (Hb <11 g/dL) 1

Special Considerations

Monitoring and Follow-up

• Monitor blood pressure in both supine and standing positions 1
• Follow-up within 1-2 weeks for symptomatic patients 1
• Monitor for supine hypertension, a common complication of treatment 1, 2
• Monitor serum potassium levels when using fludrocortisone 1
• Assess renal function prior to initiating midodrine 2

Supine Hypertension Management

• Midodrine can cause marked elevation of supine blood pressure (>200 mmHg systolic) 2
• Prevent supine hypertension by:
  • Taking last dose of midodrine 3-4 hours before bedtime 2
  • Sleeping with head of bed elevated 2
  • Reducing fludrocortisone dose or decreasing salt intake if using both medications 2

Drug Interactions

• Use caution when combining midodrine with:
  • Cardiac glycosides (may enhance bradycardia) 2
  • Other vasoconstrictors (phenylephrine, ephedrine, etc.) 2
  • MAO inhibitors or linezolid (avoid concomitant use) 2
  • Alpha-adrenergic blockers (prazosin, terazosin, doxazosin) can antagonize midodrine effects 2

Population-Specific Considerations

• Diabetic patients: Focus on glucose control in addition to OH management 1
• Heart failure patients: Start beta-blockers and ACE inhibitors/ARBs at very low doses 1
• Elderly patients: Consider long-acting dihydropyridine CCBs or RAS inhibitors as initial therapy 1
• Pregnant patients: Use volume expansion with IV fluids for acute management 1
• Patients with renal impairment: Use midodrine with caution, starting at lower doses 2
• Patients with urinary retention: Use midodrine cautiously as it acts on alpha-adrenergic receptors of the bladder neck 2

Treatment Goals

• The goal is to improve standing BP to minimize symptoms and improve standing time for daily activities, without causing excessive supine hypertension 3
• Focus on improving symptoms and functional status rather than targeting arbitrary BP values 4