How to manage a patient with orthostatic hypotension?

Management of Orthostatic Hypotension

Start by identifying and discontinuing culprit medications—particularly diuretics, alpha-1 blockers (doxazosin, prazosin, terazosin, tamsulosin), and vasodilators—as drug-induced autonomic failure is the most frequent cause of orthostatic hypotension. 1

Diagnostic Confirmation

• Measure blood pressure after 5 minutes of lying or sitting, then at 1 and 3 minutes after standing 1, 2
• Document the exact systolic and diastolic drop (orthostatic hypotension is defined as ≥20 mmHg systolic or ≥10 mmHg diastolic decrease) 2, 3
• Record heart rate response: minimal increase (<15 bpm) suggests neurogenic causes, while ≥15 bpm increase suggests non-neurogenic orthostatic hypotension 2

Identify and Eliminate Reversible Causes

Switch medications that worsen orthostatic hypotension to alternative therapy rather than simply reducing doses. 1

High-Priority Medications to Discontinue:

• Alpha-1 blockers (doxazosin, prazosin, terazosin, tamsulosin) are the most problematic agents in older adults and should be stopped immediately 1, 4
• Diuretics cause orthostatic hypotension through volume depletion and are among the most frequent culprits 1, 4
• Vasodilators (hydralazine, minoxidil) and centrally-acting agents (clonidine, methyldopa) should be discontinued 1, 4
• Beta-blockers should be avoided unless compelling indications exist 1, 4

Preferred Antihypertensive Alternatives (if blood pressure control needed):

• Long-acting dihydropyridine calcium channel blockers (amlodipine) are first-line for patients requiring continued antihypertensive therapy 1, 4
• RAS inhibitors (ACE inhibitors or ARBs) have minimal impact on orthostatic blood pressure 4

Non-Pharmacological Management (First-Line for All Patients)

Dietary Modifications:

• Increase fluid intake to 2-3 liters daily unless contraindicated by heart failure 1, 2
• Increase salt intake to 6-9 grams daily if not contraindicated 1, 2
• Eat smaller, more frequent meals to reduce postprandial hypotension 1, 2
• Avoid alcohol, which causes both autonomic neuropathy and volume depletion 1

Physical Maneuvers:

• Teach leg crossing, squatting, stooping, and muscle tensing during symptomatic episodes (particularly effective in patients under 60 years with prodromal symptoms) 1, 2
• Use waist-high compression stockings (30-40 mmHg) and abdominal binders to reduce venous pooling 1, 2
• Elevate the head of bed by 10 degrees during sleep to prevent nocturnal polyuria and ameliorate supine hypertension 1, 2
• Advise acute water ingestion (≥480 mL) for temporary relief, with peak effect at 30 minutes 1

Pharmacological Treatment (When Non-Pharmacological Measures Fail)

The therapeutic goal is minimizing postural symptoms rather than restoring normotension. 1

First-Line Medications:

Midodrine has the strongest evidence base among pressor agents with three randomized placebo-controlled trials demonstrating efficacy 1, 5:

• Starting dose: 2.5-5 mg orally three times daily 1, 2, 5
• Titrate up to 10 mg three times daily based on response 1
• Last dose must be taken at least 3-4 hours before bedtime (not after 6 PM) to prevent supine hypertension during sleep 1, 2, 5
• Increases standing systolic blood pressure by 15-30 mmHg for 2-3 hours 1, 5
• Monitor for supine hypertension (blood pressure >200 mmHg systolic can occur) 5

Fludrocortisone (alternative or adjunctive first-line agent) 1, 2:

• Starting dose: 0.05-0.1 mg orally once daily 1, 2
• Titrate to 0.1-0.3 mg daily based on response (maximum 1.0 mg daily) 1
• Acts through sodium retention and vessel wall effects 1
• Contraindicated in active heart failure or severe supine hypertension 1
• Monitor for hypokalemia, peripheral edema, and supine hypertension 1, 2
• Check electrolytes periodically due to mineralocorticoid effects 1

Droxidopa (FDA-approved for neurogenic orthostatic hypotension) 1, 2:

• Particularly effective for Parkinson's disease, pure autonomic failure, and multiple system atrophy 1, 2
• May reduce falls in neurogenic orthostatic hypotension 1

Second-Line/Refractory Cases:

Combination therapy with midodrine and fludrocortisone for non-responders to monotherapy 1:

• The medications work through complementary mechanisms (alpha-1 adrenergic stimulation vs. sodium retention) 1
• Monitor closely for supine hypertension with combination therapy 1

Pyridostigmine for refractory cases 1, 2:

• Dose: 60 mg orally three times daily (maximum 600 mg daily) 1
• Beneficial in elderly patients refractory to other treatments with a favorable side effect profile 1
• Does not worsen supine hypertension, making it ideal when supine hypertension is a concern 1
• Common side effects include nausea, vomiting, abdominal cramping, sweating, and salivation 1

Monitoring and Follow-Up

• Reassess within 1-2 weeks after medication changes 1, 2
• Measure both supine and standing blood pressure at each visit to detect treatment-induced supine hypertension 1, 2
• Monitor orthostatic vital signs at each follow-up visit 2
• If using fludrocortisone, check electrolytes, BUN, and creatinine periodically 2

Critical Pitfalls to Avoid

• Do not simply reduce the dose of offending medications—switch to alternatives 1
• Do not administer midodrine after 6 PM to avoid nocturnal supine hypertension 1, 2
• Do not use fludrocortisone in patients with heart failure or pre-existing supine hypertension 1
• Do not combine multiple vasodilating agents (ACE inhibitors + calcium channel blockers + diuretics) without careful monitoring 1
• Do not overlook volume depletion as a contributing factor—order basic metabolic panel to assess 2
• Avoid medications that can exacerbate orthostatic hypotension including psychotropic drugs and alpha-adrenoreceptor antagonists 1