When should a patient with a headache be referred to neurology?

When to Refer to Neurology for Headache

Patients with headache should be referred to neurology when there are "red flag" symptoms suggesting a secondary cause, when headaches are refractory to first-line treatments, or when specific primary headache disorders require specialist management.

Indications for Urgent/Emergency Neurological Referral

Red Flag Symptoms

• Thunderclap headache: Sudden onset, reaching maximum intensity within seconds to minutes 1
• New neurological deficits: Focal weakness, sensory changes, visual disturbances, or speech difficulties 1
• Altered mental status or abnormal neurological examination 1
• Headache that awakens patient from sleep 1
• Headache worsened by Valsalva maneuver 1
• Abrupt onset of severe headache 1
• Marked change in previous headache pattern 1
• New headache in patients >50 years old 1
• Headache in immunocompromised patients or those with cancer 1
• Persistent headache following head trauma 1

Timing of Referral

• Emergency (immediate): Thunderclap headache, altered mental status, focal neurological deficits
• Urgent (within 48 hours): New-onset headache in high-risk populations, rapidly increasing frequency of headache, headache with concerning features but stable patient 1

Indications for Non-Urgent Neurological Referral

Refractory Primary Headaches

• Migraine: Failure to respond to appropriate first-line treatments (NSAIDs, triptans) 1
• Tension-type headache: Inadequate response to standard analgesics and lifestyle modifications 1
• Medication overuse headache: Headache occurring ≥15 days/month with regular use of acute headache medications 2

Specific Primary Headache Disorders

• Cluster headache: All patients with suspected cluster headache should be referred to neurology due to specialized treatment requirements 1, 3
• Migraine with persistent aura 3
• Migraine with motor weakness (hemiplegic migraine) 3
• Trigeminal autonomic cephalalgias (other than cluster headache) 4

Other Indications

• Diagnostic uncertainty: When the headache type cannot be clearly categorized 3
• Headache with disability: Significant impact on daily functioning despite appropriate primary care management 4
• Need for specialized treatments: When treatments requiring specialist supervision are indicated (e.g., onabotulinumtoxinA, CGRP antagonists) 5

Neuroimaging Considerations

When to Order Neuroimaging Before Referral

• Neuroimaging (CT or MRI) is indicated when:
  • Patient presents with any red flag symptoms listed above 1
  • Headache with atypical features or not meeting strict definition of primary headache 1
  • Unexplained abnormal findings on neurological examination 1

When Neuroimaging May Not Be Necessary

• Patients with a normal neurological examination and typical features of primary headache disorders (migraine, tension-type headache) 1, 6
• Patients with long-standing stable pattern of primary headache without new features 6

Common Pitfalls to Avoid

1. Overuse of neuroimaging: Ordering brain imaging for all headache patients leads to unnecessary radiation exposure, incidental findings, and healthcare costs 2, 6

2. Delayed referral for patients with red flags or concerning features, which can lead to missed diagnoses of serious secondary causes 1

3. Failure to recognize medication overuse headache: Patients using analgesics (including over-the-counter) for ≥15 days/month may develop medication overuse headache requiring specialist management 2

4. Inappropriate treatment: Prescribing opioids or benzodiazepines for headache management, which can lead to dependence and worsening of headache patterns 2

5. Missing secondary headaches: Approximately 10% of patients referred to specialty headache clinics have secondary headaches that require specific treatment 2

By following these guidelines, primary care physicians can ensure appropriate and timely referral of headache patients to neurology, optimizing patient outcomes while avoiding unnecessary specialist consultations.