What are the appropriate next steps for a patient who awakens with headaches, possibly indicating a primary headache disorder or a more severe condition such as subarachnoid hemorrhage or meningitis?

Awakening with Headaches: Diagnostic and Management Approach

For a patient who awakens with headaches, immediately assess for life-threatening causes—particularly subarachnoid hemorrhage (SAH), meningitis, or space-occupying lesions—before attributing symptoms to benign primary headache disorders, as headaches that awaken patients from sleep represent a red flag requiring urgent evaluation. 1, 2

Immediate Risk Stratification

Critical Red Flags Requiring Emergency Evaluation

When a patient reports awakening with headaches, the following features mandate urgent investigation:

• Thunderclap onset (reaching maximum intensity within seconds to 1 minute) suggests SAH and requires immediate neuroimaging 1, 3, 2
• "Worst headache of life" or marked change from previous headache pattern indicates possible vascular pathology 2, 1
• New onset after age 50 raises concern for temporal arteritis or secondary causes 2, 4
• Progressive worsening over time suggests intracranial space-occupying lesion 2
• Associated neurological deficits (focal weakness, ataxia, dysarthria, altered consciousness) require immediate imaging 1, 3
• Neck stiffness or fever indicates possible meningitis or SAH 1, 2
• Headache aggravated by Valsalva maneuver suggests increased intracranial pressure 1, 2

Ottawa SAH Rule Application

For alert patients >15 years with new severe headache reaching maximum intensity within 1 hour, additional investigation is required if ANY of the following are present 1, 2:

• Age ≥40 years
• Neck pain or stiffness
• Witnessed loss of consciousness
• Onset during exertion
• Thunderclap headache (instantly peaking pain)
• Limited neck flexion on examination

Diagnostic Algorithm

Neuroimaging Decision Pathway

For patients presenting >6 hours from symptom onset OR with any new neurological deficit:

• Obtain noncontrast head CT immediately 1, 3, 2
• If CT is negative but clinical suspicion remains high, perform lumbar puncture with CSF spectrophotometric analysis for xanthochromia, ideally >12 hours from onset 1, 3

For patients presenting <6 hours from symptom onset WITHOUT new neurological deficit:

• Noncontrast head CT on high-quality scanner interpreted by board-certified neuroradiologist is reasonable to diagnose/exclude SAH 1, 3

If both CT and LP are negative but high suspicion persists:

• Consider digital subtraction angiography (DSA) to diagnose/exclude cerebral aneurysm 1, 3
• Note that CT angiography has ~97% sensitivity for ruptured aneurysms but does not directly evaluate for SAH 1, 5

Critical Diagnostic Pitfalls to Avoid

• Never rely on symptom quality alone to differentiate benign from dangerous causes 3
• Do not assume young age excludes SAH, as 20% of patients experience sentinel headaches before catastrophic rupture 1, 5
• Misdiagnosis is associated with nearly 4-fold higher likelihood of death or disability at 1 year in patients with minimal neurological deficit 1
• The most common diagnostic error is failure to obtain noncontrast cranial CT 1

Management Based on Etiology

If SAH is Confirmed

• Transfer immediately to tertiary center with neurosurgical expertise 3
• Start nimodipine within 96 hours 3
• Secure aneurysm urgently via endovascular coiling or surgical clipping 3
• Mortality exceeds 40% at 30 days without prompt intervention 3

If Primary Headache Disorder is Diagnosed

For migraine attacks awakening patient from sleep:

• Use NSAIDs as first-line for mild-to-moderate attacks 1, 3
• Consider triptans for moderate-to-severe attacks, but avoid in patients with multiple cardiovascular risk factors without prior cardiovascular evaluation 6
• Sumatriptan is contraindicated in patients with coronary artery disease, Prinzmetal's angina, uncontrolled hypertension, or history of stroke/TIA 6

Critical medication-overuse headache prevention:

• Limit acute headache medications to ≤2 days per week to prevent medication-overuse headache, which can transform episodic migraine into chronic daily headache 3, 6
• Frequent use of triptans, ergotamine, opioids, or analgesics (≥10 days per month) may cause rebound headaches 1, 6

Preventive Therapy Consideration

• Consider preventive therapy if patient has >2 headaches per week 1
• This approach helps avoid medication-overuse headache and improves quality of life 1

Essential Clinical Documentation

Document the following specific features 3, 2, 4:

• Timing: Exact time of awakening, duration until maximum intensity
• Character: Quality (throbbing, pressing, stabbing), severity (0-10 scale)
• Location: Unilateral vs bilateral, specific regions affected
• Associated symptoms: Nausea, vomiting, photophobia, phonophobia, visual changes
• Neurological examination: Mental status, cranial nerves, motor/sensory function, coordination, gait, neck stiffness
• Vital signs: Blood pressure (hypertensive crisis can cause headache), temperature (fever suggests infection)

When Neuroimaging is NOT Warranted

In patients with normal neurological examination and headache that meets strict criteria for primary headache disorder (migraine, tension-type, cluster) without atypical features, neuroimaging is usually not warranted 1. However, headaches awakening patients from sleep lower this threshold and should prompt consideration of imaging 1, 2.