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Approach to the Patient With Headache


Stephen D. Silberstein

, MD, Sidney Kimmel Medical College at Thomas Jefferson University

Reviewed/Revised Apr 2023
Topic Resources

Headache is pain in any part of the head, including the scalp, face (including the orbitotemporal area), and interior of the head. Headache is one of the most common reasons patients seek medical attention.

Pathophysiology of Headache

Headache is due to activation of pain-sensitive structures in or around the brain, skull, face, sinuses, or teeth.

Etiology of Headache

Headache may occur as a primary disorder or be secondary to another disorder.

Primary headache disorders include the following:

Secondary headache has numerous causes (see table Disorders Causing Secondary Headache Disorders Causing Secondary Headache Disorders Causing Secondary Headache ).

Overall, the most common causes of headache are

  • Tension-type headache

  • Migraine

Some causes of headache are common; others are important to recognize because they are dangerous, require specific treatment, or both (see table Some Characteristics of Headache Disorders by Cause Some Characteristics of Headache Disorders by Cause Some Characteristics of Headache Disorders by Cause ).


Evaluation of Headache

Evaluation of headache focuses on

  • Determining whether a secondary headache is present

  • Checking for symptoms that suggest a serious underlying disorder

If no cause or serious symptoms are identified, evaluation focuses on diagnosing primary headache disorders.


History of present illness includes questions about the headache's characteristics:

  • Location

  • Duration

  • Severity

  • Onset (eg, sudden, gradual)

  • Quality (eg, throbbing, constant, intermittent, pressure-like)

Exacerbating and remitting factors (eg, head position, time of day, sleep, light, sounds, physical activity, odors, chewing) are noted. Patients are asked whether headaches occur only when standing; such headaches are a concern because they may be caused by a cerebrospinal fluid (CSF) leak or postural orthostatic tachycardia syndrome (POTS). If the patient has had previous or recurrent headaches, the previous diagnosis (if any) needs to be identified, and whether the current headache is similar or different needs to be determined. For recurrent headaches, the following are noted:

  • Age at onset

  • Frequency of episodes

  • Temporal pattern (including any relationship to phase of menstrual cycle)

  • Response to treatments (including over-the-counter treatments)

Review of systems should seek symptoms suggesting a cause, including

Past medical history should identify risk factors for headache, including use of medications or substances (particularly caffeine), withdrawal of caffeine, exposure to toxins (see table Disorders Causing Secondary Headache Disorders Causing Secondary Headache Disorders Causing Secondary Headache ), recent lumbar puncture, use of immunosuppressants or IV drugs (risk of infection), hypertension (risk of brain hemorrhage), cancer (risk of brain metastases), dementia, trauma, coagulopathy, or use of anticoagulants or ethanol (risk of subdural hematoma).

Family and social history should include any family history of headaches, particularly because migraine headache may be undiagnosed in family members.

To streamline data collection, clinicians can ask patients to fill out a headache questionnaire that covers most of the relevant medical history pertinent to diagnosis of headache. Patients may complete the questionnaire before their visit and bring the results with them.

Physical examination

Vital signs, including temperature, are measured. General appearance (eg, whether restless or calm in a dark room) is noted. A general examination, with a focus on the head and neck, and a full neurologic examination Introduction to the Neurologic Examination The purpose of the neurologic examination is to establish whether the patient’s brain, special senses, spinal cord, peripheral nerves, and muscle and skin receptors are functioning normally... read more are done.

The scalp is examined for areas of swelling and tenderness. The ipsilateral temporal artery is palpated, and both temporomandibular joints are palpated for tenderness and crepitance while the patient opens and closes the jaw.

The eyes and periorbital area are inspected for lacrimation, flushing, and conjunctival injection. Pupillary size and light responses, extraocular movements, and visual fields are assessed. The fundi are checked for spontaneous retinal venous pulsations and papilledema Papilledema Papilledema is swelling of the optic disk due to increased intracranial pressure. Optic disk swelling resulting from causes that do not involve increased intracranial pressure (eg, malignant... read more Papilledema . If patients have vision-related symptoms or eye abnormalities, visual acuity is measured. If the conjunctiva is red, the anterior chamber and cornea are examined with a slit lamp if possible, and intraocular pressure is measured.

The nares are inspected for purulence. The oropharynx is inspected for swellings, and the teeth are percussed for tenderness.

Neck is flexed to detect discomfort, stiffness, or both, indicating meningismus. The cervical spine is palpated for tenderness.

Red flags

The following findings are of particular concern:

  • Neurologic symptoms or signs (eg, altered mental status, weakness, diplopia, papilledema, focal neurologic deficits)

  • Severe hypertension

  • Immunosuppression or cancer

  • Meningismus

  • Onset of headache after age 50

  • Thunderclap headache (severe headache that peaks within a few seconds)

  • Symptoms of giant cell arteritis (eg, visual disturbances, jaw claudication, fever, weight loss, temporal artery tenderness, proximal myalgias)

  • Systemic symptoms (eg, fever, weight loss)

  • Progressively worsening headache

  • Red eye and halos around lights

Interpretation of findings

If similar headaches recur in patients who appear well and have a normal examination, the cause is rarely ominous. Headaches that have recurred since childhood or young adulthood suggest a primary headache disorder. If headache type or pattern clearly changes in patients with a known primary headache disorder, secondary headache should be considered.

Most single symptoms of primary headache disorders other than aura are nonspecific. A combination of symptoms and signs is more characteristic (see table Some Characteristics of Headache Disorders by Cause Some Characteristics of Headache Disorders by Cause Some Characteristics of Headache Disorders by Cause ).



Most patients can be diagnosed without testing. However, some serious disorders may require urgent or immediate testing. Some patients require tests as soon as possible.

MRI (and perhaps magnetic resonance angiography [MRA]) should be done as soon as possible in patients with any of the following findings:

If MRI is not immediately available, CT can be used.

Also, neuroimaging, usually MRI, should be done if patients have any of the following:

  • Focal neurologic deficit of subacute or uncertain onset

  • New onset

  • Age > 50 years

  • Cancer

  • HIV infection or AIDS

  • Change in an established headache pattern

  • Diplopia

Other testing should be done within hours or days, depending on the acuity and seriousness of findings and suspected causes.

Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) should be determined if patients have visual symptoms, jaw or tongue claudication, temporal artery signs, or other findings suggesting giant cell arteritis.

CT of the paranasal sinuses is done to rule out complicated sinusitis Sinusitis Sinusitis is inflammation of the paranasal sinuses due to viral, bacterial, or fungal infections or allergic reactions. Symptoms include nasal obstruction and congestion, purulent rhinorrhea... read more Sinusitis if patients have a moderately severe systemic illness (eg, high fever, dehydration, prostration, tachycardia) and findings suggesting sinusitis (eg, frontal, positional headache; epistaxis; purulent rhinorrhea).

Treatment of Headache

Treatment of headache is directed at the cause.

Geriatrics Essentials: Headache

New-onset headache after age 50 should be considered a secondary disorder until proven otherwise.

Key Points

  • Recurrent headaches that began at a young age in patients with a normal examination are usually benign.

  • Neuroimaging is recommended as soon as possible for patients with altered mental status, seizures, papilledema, focal neurologic deficits, or thunderclap headache.

  • CSF analysis is required after neuroimaging for patients with meningismus and usually for immunosuppressed patients and those with papilledema.

  • Patients with thunderclap headache require CSF analysis even if neuroimaging and examination findings are normal as long as lumbar puncture is not contraindicated by imaging results.

Drugs Mentioned In This Article

Drug Name Select Trade
Cafcit, NoDoz, Stay Awake, Vivarin
NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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