What are the next steps in managing a middle-aged adult with orthostatic headaches, dizziness, and nausea, with no significant past medical history, after Spontaneous Intracranial Hypotension (SIH) has been ruled out?

Management After SIH Has Been Ruled Out

When orthostatic headaches, dizziness, and nausea persist in a middle-aged adult after SIH has been definitively excluded, immediately evaluate for Postural Orthostatic Tachycardia Syndrome (PoTS) with a formal standing test and orthostatic hypotension with serial blood pressure measurements, as these are the most common alternative diagnoses that present with identical orthostatic symptoms. 1

Mandatory Differential Diagnoses to Pursue

Postural Orthostatic Tachycardia Syndrome (PoTS)

• Perform a formal standing test measuring heart rate and blood pressure at baseline supine, then at 2,5, and 10 minutes of standing 1
• PoTS is diagnosed when heart rate increases ≥30 bpm (or ≥40 bpm in adolescents) within 10 minutes of standing without orthostatic hypotension 1
• This condition produces identical orthostatic symptoms to SIH but requires entirely different management 1

Orthostatic Hypotension

• Document blood pressure drops: ≥20 mmHg systolic or ≥10 mmHg diastolic within 3 minutes of standing 1
• If confirmed, consider midodrine 10 mg three times daily (last dose before 6 PM) to increase standing systolic pressure by 15-30 mmHg 2
• Midodrine is specifically indicated for symptomatic orthostatic hypotension when lives are considerably impaired despite non-pharmacologic measures 2

Cervicogenic Headache

• Assess whether headache is provoked by cervical movement rather than purely by posture 1
• Examine for neck tenderness, restricted cervical range of motion, and reproduction of headache with neck palpation 1

Critical Timing Verification

Even with SIH ruled out, verify the orthostatic pattern meets these specific criteria to guide further workup:

• Headache absent or mild upon waking 1
• Onset within 2 hours of becoming upright 1
• Improvement by >50% within 2 hours of lying flat 1
• Consistent timing pattern across episodes 1

If the headache pattern does NOT meet these strict timing requirements, reconsider primary headache disorders (migraine, tension-type headache) rather than pursuing orthostatic etiologies. 1

Associated Symptom Assessment

Document the presence and severity of:

• Nausea and vomiting (present in 28% of orthostatic conditions) 1
• Neck pain or stiffness 3, 4
• Tinnitus or hearing changes (11% of cases) 1
• Visual disturbances (3% of cases) 1
• Vertigo (8% of cases) 1

Conservative Management Trial

Before pursuing advanced interventions, implement:

• Increased fluid intake (2-3 liters daily) 5, 4
• Increased salt intake (unless contraindicated) 5
• Compression stockings 2
• Gradual position changes 2
• Caffeine supplementation 5

When to Escalate Care

Refer to neurology or autonomic specialist if:

• Symptoms persist despite 2-4 weeks of conservative management 6
• Progressive neurological symptoms develop 6
• Significant functional impairment continues 2
• Diagnostic uncertainty remains after initial workup 6

Common Pitfall to Avoid

Do not assume all orthostatic headaches are SIH—the differential diagnosis is broad, and misdiagnosis leads to inappropriate treatment that can worsen outcomes. 1 Many conditions mimic SIH's orthostatic pattern, and each requires distinct management strategies. The formal standing test for PoTS and blood pressure monitoring for orthostatic hypotension are simple bedside tests that should be performed before pursuing more invasive or expensive evaluations 1.