What is the appropriate initial assessment and management for a patient presenting with headache, including red‑flag evaluation, acute therapy, and preventive strategies?

Initial Assessment of Headache

Begin by immediately screening for red-flag features that indicate life-threatening secondary causes requiring urgent neuroimaging or emergency referral. 1, 2

Red-Flag Assessment (Perform First)

Critical Red Flags Requiring Immediate Action

• Thunderclap headache (sudden onset reaching maximum intensity within seconds to minutes) suggests subarachnoid hemorrhage and requires non-contrast head CT within 6 hours, followed by lumbar puncture if CT is negative 1, 2
• "Worst headache of life" with abrupt onset indicates serious vascular pathology 1
• New neurological deficits (focal weakness, sensory changes, visual field defects, altered consciousness) mandate immediate neuroimaging with MRI preferred over CT 1, 2
• Fever with neck stiffness suggests meningitis or subarachnoid hemorrhage and requires urgent lumbar puncture 1
• New headache after age 50 increases risk of temporal arteritis (15% risk), subdural hematoma, or neoplasm—obtain ESR/CRP and neuroimaging 1, 2

Additional Red Flags Warranting Investigation

• Progressive worsening pattern over days to weeks suggests space-occupying lesion 1
• Headache awakening patient from sleep may indicate increased intracranial pressure 3, 1
• Worsened by Valsalva, cough, or positional changes suggests increased intracranial pressure from mass lesion 1, 2
• Persistent headache following head trauma may indicate intracranial injury 3, 1
• Marked change in previously stable headache pattern is a red flag for secondary headache 1

Ottawa SAH Rule (for severe nontraumatic headache reaching maximum intensity within 1 hour)

Additional investigation required if any of: age ≥40 years, neck pain/stiffness, witnessed loss of consciousness, onset during exertion, thunderclap headache, or limited neck flexion on examination 1

Focused History Elements

Obtain specific details to differentiate primary headache types and identify secondary causes. 3, 2

Essential Questions to Ask

• Frequency and duration: Chronic migraine defined as ≥15 headache days per month for >3 months with ≥8 days having migraine features 3, 2
• Time to maximum intensity: Instantaneous suggests SAH; gradual over hours suggests migraine 1
• Pain location: Unilateral suggests migraine or cluster; bilateral suggests tension-type 3, 2
• Pain character: Throbbing suggests migraine; pressing/tightening suggests tension-type 3
• Pain severity: Moderate-to-severe suggests migraine; mild-to-moderate suggests tension-type 3
• Duration of individual attacks: Migraine 4-72 hours; cluster 15-180 minutes; tension-type variable 3, 2
• Associated symptoms: Nausea/vomiting, photophobia, phonophobia suggest migraine; autonomic symptoms (lacrimation, nasal congestion, ptosis) suggest cluster headache 3
• Aura symptoms: Visual, sensory, or speech disturbances spreading gradually over ≥5 minutes suggest migraine with aura 3
• Aggravating factors: Routine physical activity worsens migraine but not tension-type 3
• Current medication use: Document frequency of acute medication use (critical for identifying medication-overuse headache) 3, 2
• Family history: Positive family history strengthens suspicion of migraine 3

Physical and Neurological Examination

Perform targeted examination focusing on findings that indicate secondary causes. 3

Key Examination Components

• Vital signs: Fever suggests infection; hypertension may indicate hypertensive emergency 1
• Neurological examination: Assess mental status, cranial nerves, motor/sensory function, coordination, gait, and reflexes—any abnormality warrants neuroimaging 3, 1
• Neck examination: Check for stiffness (meningitis/SAH), limited flexion (Ottawa SAH Rule), and temporal artery tenderness (temporal arteritis) 1
• Fundoscopic examination: Papilledema indicates increased intracranial pressure 4
• Palpation: Assess for scalp/muscle tenderness, sinus tenderness 3

A normal neurological examination in a patient with typical primary headache features and no red flags usually does not warrant neuroimaging. 3

Diagnostic Testing Indications

When to Order Neuroimaging

Neuroimaging is indicated when red flags are present or when headache has atypical features not meeting strict criteria for primary headache. 3, 1

• MRI preferred over CT due to higher resolution and absence of radiation exposure, except when acute intracranial hemorrhage is suspected 1
• CT without contrast recommended when acute hemorrhage suspected (thunderclap headache, trauma) 1
• Neuroimaging NOT routinely indicated for patients with normal neurological examination and headache meeting strict criteria for primary headache without atypical features 3

When to Perform Lumbar Puncture

• After negative CT in suspected subarachnoid hemorrhage presenting >6 hours from onset 1
• Suspected meningitis or encephalitis with fever and neck stiffness 2
• Suspected high or low CSF pressure syndromes 5

Acute Management Based on Headache Type

For Episodic Migraine (Mild-to-Moderate)

First-line options include NSAIDs (ibuprofen 400-800 mg, naproxen sodium 275-550 mg) or combination analgesics containing aspirin, acetaminophen, and caffeine. 3, 2, 6

• Acetaminophen alone is NOT recommended for migraine 3
• Administer as early as possible during attack for improved efficacy 3
• Ketorolac 60 mg IM may be used for severe attacks in office/ED setting 3

For Episodic Migraine (Moderate-to-Severe)

Triptans are first-line therapy but require cardiovascular screening as they are contraindicated in coronary artery disease, uncontrolled hypertension, and stroke history. 2, 6

• Triptans eliminate pain in 20-30% of patients by 2 hours 6
• Adverse effects include transient flushing, tightness, or tingling in upper body in 25% of patients 6
• Alternative options: Gepants (rimegepant, ubrogepant) eliminate headache in 20% at 2 hours with nausea/dry mouth in 1-4% 6
• Lasmiditan (5-HT1F agonist) appears safe in patients with cardiovascular risk factors 6

For Cluster Headache

Acute treatment includes subcutaneous sumatriptan 6 mg and 100% oxygen at 12 L/min via non-rebreather mask. 2

Adjunctive Therapy

• Metoclopramide for nausea and improved gastric motility 3
• Prochlorperazine can effectively relieve headache pain 3

Preventive Therapy Indications

Initiate preventive therapy if patient has ≥2 headaches per week, uses acute medications >10 days per month, or meets criteria for chronic migraine. 3, 2

First-Line Preventive Options

• For episodic migraine: Propranolol 80-240 mg/day, timolol 20-30 mg/day, topiramate, or amitriptyline (especially for mixed migraine/tension-type) 2
• For chronic migraine: OnabotulinumtoxinA (only FDA-approved therapy for chronic migraine prophylaxis), topiramate, or options effective in episodic migraine 2
• For cluster headache: Verapamil 360 mg/day with ECG monitoring for PR interval prolongation 2

Preventive Therapy Reduces Migraine by 1-3 Days Per Month

This modest benefit must be weighed against adverse effects and patient preference 6

Medication-Overuse Headache Management

Diagnose medication-overuse headache if patient uses simple analgesics ≥15 days/month or triptans/combination analgesics ≥10 days/month for >3 months. 3, 2

• Immediately initiate preventive therapy while detoxifying by withdrawing overused medications 2
• Avoid opioids and butalbital-containing compounds except as rare rescue medication—these are most likely to cause medication-overuse headache and reduce quality of life 3, 2

Critical Pitfalls to Avoid

• Do NOT rely solely on neuroimaging without considering complete clinical picture 1
• Do NOT prescribe opioids or butalbital compounds as first-line therapy—they promote medication-overuse headache 2
• Do NOT use β-blockers with intrinsic sympathomimetic activity—they are ineffective for migraine prevention 2
• Do NOT overlook medication-overuse headache in patients on long-term analgesics with unremitting headache 7
• Do NOT miss temporal arteritis in patients >50 years with new headache—obtain ESR/CRP urgently 2

Patient Education Requirements

• Maintain headache diary to guide management decisions 2
• Identify and avoid personal triggers 2
• Establish regular sleep patterns to reduce migraine frequency 2
• Provide preemptive education on risk of medication-overuse headache 2
• Limit simple analgesics to <15 days/month and triptans to <10 days/month 2