Headache Diagnosis and Management

Red Flags and Secondary Headaches

The American Academy of Neurology recommends that adults with headache and no significant past medical history should first rule out life-threatening secondary causes using red flag criteria, then systematically differentiate between primary headache disorders, with a strength of evidence level of B 1
Red flags include thunderclap headache, new-onset headache after age 50, progressive worsening headache, headache with Valsalva, cough, or exertion, focal neurological symptoms or signs, unexplained fever with neck stiffness, and recent head or neck trauma, according to the American College of Emergency Physicians 1, 2
The International Headache Society suggests that MRI brain with and without contrast is the preferred modality for subacute presentations, offering higher resolution without ionizing radiation, with a strength of evidence level of A 1

The American Headache Society recommends that migraine without aura be suspected when headache is unilateral, pulsating, moderate-to-severe, and accompanied by nausea/vomiting or photophobia plus phonophobia, with a duration of 4-72 hours when untreated, and requires at least 5 lifetime attacks meeting these criteria, with a strength of evidence level of A 4
The International Headache Society suggests that migraine with aura requires ≥2 attacks with fully reversible aura symptoms, with a strength of evidence level of A 4
The American Academy of Neurology recommends that tension-type headache be diagnosed when headache is bilateral, pressing or tightening quality, mild-to-moderate intensity, and not aggravated by routine physical activity, with a strength of evidence level of B 1, 4
The European Headache Federation suggests that cluster headache is a rare but highly characteristic disorder, easily distinguished by strictly unilateral orbital/periorbital/temporal pain, severe or very severe intensity, short duration, and frequency of 1-8 attacks daily during cluster periods, with a strength of evidence level of A 4, 5

The American Academy of Neurology recommends that validated screening questionnaires, such as the ID-Migraine and Migraine Screen Questionnaire, be used to diagnose migraine, with a strength of evidence level of B 2
The International Headache Society suggests that a headache diary is essential for accurate diagnosis, reducing recall bias and allowing systematic application of ICHD-3 criteria over multiple attacks, with a strength of evidence level of A 1, 2
The American College of Emergency Physicians recommends that emergency admission be considered for any red flag present, patient unable to self-care without help, with a strength of evidence level of A 2