Causes

The International Classification of Headache Disorders categorises the headache disorders into:

• Primary headaches (90%) — headaches which are not associated with another underlying condition for example:
  • Migraine (10%)
  • Tension-type headache (40%)
  • Cluster headache (1%)
• Secondary headaches — headaches which occur as a result of underlying local or systemic pathology for example:
  • Trauma or injury to the head and/or neck
  • Cranial or cervical vascular disorders such as intracerebral haemorrhage, central venous thrombosis or giant cell arteritis
  • Non-vascular intracranial disorders such as idiopathic intracranial hypertension or malignancy
  • Exposure to or withdrawal from a substance such as carbon monoxide, cocaine, opioids, ergotamines, triptans, simple analgesics, or alcohol
  • Infection including bacterial or viral meningitis
  • Disorders of homeostasis such as hypoxia or hypertension
  • Disorders of the cranium, neck, eyes, ears, nose, sinuses, teeth, mouth or other facial and cranial structures such as acute glaucoma, temporomandibular disorder or sinusitis
  • Psychiatric disorders such as somatization disorder
• Painful cranial neuropathies, other facial pains and other headaches — this group includes conditions such as trigeminal neuralgia and optic neuritis

Assessment

• History
  • Onset, duration, frequency and temporal pattern (episodic, daily or unremitting)
  • Pain characteristics including severity, site and spread of pain
  • Associated symptoms such as:
    • Aura (visual, auditory or gustatory disturbance), nausea, photophobia and intolerance of noise — may indicate migraine
    • Autonomic features for example tearing, drooping or swollen eyelid, pain around one eye, nasal congestion or rhinorrhoea — may indicate cluster headache
    • Systemic and neurological features such as fever, neck stiffness, weakness and visual disturbance
  • Contacts with similar symptoms
    • Consider possible carbon monoxide poisoning if household contacts or pets have similar symptoms
  • Precipitating and relieving factors such as:
    • Trauma, posture, Valsalva manoeuvres, fatigue or stress, menstrual cycle, and medication change or withdrawal
  • Comorbidities and past medical history including:
    • Compromised immunity, systemic illness, malignancy and pregnancy
  • Drug history
  • Effect on activities
    • Migraine is associated with withdrawal from daily activities due to incapacity
    • Tension-type headache typically has no effect on activities
    • Cluster headache is associated with agitation or restlessness
• Examination
  • Vital signs
    • Assess blood pressure, pulse, respiration rate, temperature and oxygen saturation levels.
  • General appearance and mental state
    • Look for signs of serious causes of headache such as skin rash, changes in level of consciousness or confusion.
  • Extracranial structures
    • Assess the carotid arteries, temporal arteries, sinuses and temporomandibular joints.
  • The neck
    • Look for signs of meningeal irritation, tenderness of cervical paraspinal muscles, limitation in range of movement and crepitation.
  • Neurology
    • Carry out fundoscopy (looking for papilloedema, pupillary asymmetry and reactivity) and cranial and peripheral nerve examination including gait.

Diagnostic criteria for common types of headaches

• Consider tension-type headache if:
  • The person has recurrent episodes of headache lasting from 30 minutes to 7 days which is not associated with nausea or vomiting (the headache may also be associated with no more than one of photophobia or phonophobia) and
  • The headache has at least two of:
    • Bilateral location.
    • Pressing or tightening (non-pulsating) quality.
    • Mild or moderate intensity.
    • Not aggravated by routine physical activity such as walking or climbing stairs.
• Consider migraine without aura if the person has had at least five attacks fulfilling the following criteria:
  • Headache attacks lasting 4-72 hours (untreated or unsuccessfully treated).
  • The headache has at least two of the following four characteristics:
    • Unilateral location.
    • Pulsating quality.
    • Moderate or severe pain intensity.
    • Aggravation by or causing avoidance of routine physical activity (for example walking or climbing stairs).
    • During the headache at least one of the following; nausea and/or vomiting; photophobia and phonophobia.
• Consider migraine with aura if the person has had at least two attacks fulfilling the following criteria:
  • One or more of the following fully reversible aura symptoms:
    • Visual symptoms such as zigzag lines and/or scotoma— visual aura is the most common type of aura.
    • Sensory symptoms such as pins and needles.
    • Speech and/or language symptoms such as aphasia.
    • Motor weakness.
    • Brainstem symptoms such as vertigo or diplopia.
    • Retinal symptoms such as monocular scintillations or scotoma.
  • At least two of the following four characteristics:
    • At least one aura symptom spreads gradually over at least 5 minutes, and/or two or more symptoms occur in succession.
    • Each individual aura symptom lasts 5-60 minutes.
    • At least one aura symptom is unilateral.
    • The aura is accompanied, or followed within 60 minutes, by headache.
• Consider cluster headache if:
  • The person has had at least five attacks of severe or very severe unilateral orbital, supraorbital and/or temporal pain lasting 15–180 minutes and
  • The headache is associated with at least one of: ipsilateral conjunctival injection and/or lacrimation; nasal congestion and/or rhinorrhoea; eyelid oedema; forehead and facial sweating; forehead and facial flushing; sensation of fullness in the ear; or miosis and/or a sense of restlessness or agitation.
  • Attacks occur between one every other day and eight per day for more than half of the time when the disorder is active.

Red flag features

• New severe or unexpected headache:
  • Sudden-onset severe headache reaching maximum intensity within 5 minutes may indicate serious causes such as intracranial haemorrhage, venous sinus thrombosis, hypertensive encephalopathy and vertebral artery dissection.
  • New onset headache in a person aged over 50 years may indicate a serious cause such as giant cell arteritis or space occupying lesion.
• Progressive or persistent headache or headache that has changed dramatically:
  • Consider serious causes such as mass lesion or subdural haematoma.
• Associated features such as:
  • Fever, impaired consciousness, seizure, neck pain/stiffness or photophobia — consider serious causes such as meningitis and encephalitis.
  • Papilloedema — consider space occupying lesions, cerebral venous sinus thrombosis and benign intracranial hypertension.
  • New-onset neurological deficit, change in personality and new-onset cognitive dysfunction — consider serious causes such as a cerebrovascular event, malignancy or other space occupying lesions such as subacute or chronic subdural hematoma.
  • Atypical aura (duration greater than 1 hour, or including motor weakness) or aura occurring for the first time in a patient during use of combined oral contraceptives — consider serious causes such as cerebrovascular event.
  • Dizziness — consider serious causes such as ischaemic or haemorrhagic stroke.
  • Visual disturbance — can be associated with migraine but also with serious causes such as acute closure glaucoma and temporal arteritis.
  • Vomiting — can associated with migraine but may also be associated with a serious cause of headache such as mass lesion, brain abscess, or carbon monoxide poisoning.
• Contacts with similar symptoms
  • Consider serious causes such as carbon monoxide poisoning if household contacts have similar symptoms.
• Precipitating factors such as:
  • Preceding recent (usually within the past 3 months) head trauma — consider serious causes such as subacute or chronic subdural hematoma.
  • Headache triggered by a Valsalva manoeuvre (such as coughing, sneezing, bending or exertion [physical or sexual]) — consider serious causes such as Chiari 1 malformation or a posterior fossa lesion.
  • Headache that worsens on standing — consider a CSF leak.
  • Headache that worsens on lying down — consider a space-occupying lesion or cerebral venous sinus thrombosis.
• Comorbidities such as:
  • Compromised immunity (for example due to HIV or immunosuppressive drugs) — consider serious causes such as cerebral infection or malignancy.
  • Current or past malignancy — consider serious causes such as cerebral metastases.
• Current or recent pregnancy — consider serious causes such as pre-eclampsia.

Management of common types of headache

• Tension-type headache (TTH)
  • Offer simple analgesia such as paracetamol, aspirin or a nonsteroidal anti-inflammatory taking into account comorbidities and risk of adverse effects — advise the person to take a therapeutic dose as soon as possible after onset of attack. Do not offer opioids — if needed, reconsider the diagnosis.
  • Identify comorbidities that may be associated with TTH such as stress, mood disorders, chronic pain and sleep disorders and manage appropriately.
  • If clinical features are consistent with chronic TTH, treatment options include a course of acupuncture, or pharmacological prophylaxis with low dose amitriptyline.
• Migraine
  • Avoidance of known triggers and lifestyle changes such as stress management, good sleep hygiene, adequate hydration, regular meals, exercise, and maintenance of a healthy weight can help.
  • Management of acute migraine:
    • Depending on the severity of attacks, associated symptoms, contraindications and comorbidities:
    • Offer simple analgesia such as:
      • Ibuprofen (400mg) — if ineffective, consider increasing to 600 mg or
      • Aspirin (900 mg) or
      • Paracetamol (1000mg).
    • Offer a triptan, alone or in combination with, paracetamol or an NSAID:
      • Oral sumatriptan (50–100 mg) is first choice — other triptans should be offered if sumatriptan fails.
      • If vomiting restricts oral treatment, consider a non-oral formulation (such as intra-nasal or subcutaneous).
    • Consider offering an antiemetic (such as metoclopramide 10mg or prochlorperazine 10 mg) in addition to other acute medication even in the absence of nausea and vomiting. Metoclopramide should not be used regularly due to the risk of extrapyramidal side effects.
    • Do NOT offer ergots or opioids.
  • Preventative treatment:
    • The aim of preventive treatment is to reduce the frequency, severity, and duration of migraine attacks, and avoid medication-overuse headache. Choice of preventative medication depends on contraindications, comorbidities, and risk of adverse events.
    • Pharmacological treatment options include propranolol, topiramate or amitriptyline. Non-pharmacological treatment options include behavioural interventions, acupuncture or riboflavin.
• Cluster headache
  • People presenting with a first bout of cluster headache should be referred to a neurologist — confirmation of diagnosis by a specialist is required and may involve neuroimaging. Preventative treatment (such as verapamil) may be considered.
  • Management of acute bouts of confirmed cluster headache:
    • If appropriate, offer a subcutaneous or nasal triptan to people aged over 18 years e.g. sumatriptan by subcutaneous injection (initially 6mg for 1 dose, followed by further 6 mg after at least 1 hour if headache recurs), or sumatriptan by intranasal administration (initially 10-20mg dose, followed by further 10-20mg after at least 2 hours if headache recurs).
    • Do not offer paracetamol, nonsteroidal anti-inflammatories, opioids, ergots or oral triptans for the acute treatment of cluster headache.
    • Offer short burst oxygen therapy - if not contraindicated, provide 100% oxygen at a flow rate of 12–15 litres per minute via a non-rebreather face mask for 15 to 20 minutes.
    • Advise the person on avoidance of triggers: Cluster attacks may be triggered or exacerbated by behaviours such as alcohol consumption and smoking.

Trigeminal neuralgia

• Trigeminal neuralgia is typically defined as severe, episodic facial pain, in the distribution of one or more branches of the fifth (trigeminal) cranial nerve. Typically, the maxillary or mandibular branches are affected, either alone or in combination. Involvement of the ophthalmic branch alone is uncommon.
• In around 95% of cases, trigeminal neuralgia is thought to be caused by vascular compression of the trigeminal nerve, leading to central demyelination of the nerve root entry zone, reinforced electrical excitability, and impairment of the nociceptive system.
• Risk factors include: multiple sclerosis, advancing age, female sex, family history, hypertension and stroke.
• Suspect trigeminal neuralgia if the person has pain in the distribution of the trigeminal nerve (usually in the cheek or lower jaw) that is:
  • Severe — often described as electric shock-like, sharp, or shooting.
  • Unilateral — trigeminal neuralgia is bilateral in only 3% of people.
  • Short-lived — lasting a few seconds to minutes and stopping suddenly.
  • Recurrent — the person may experience many attacks a day, with a refractory period between each attack.
  • Episodic — the pain may go into remission for weeks or months before returning.
  • Provoked by factors such as light touch to the face, eating, talking, or exposure to cold air.
• Be aware of serious conditions which can lead to compression of the trigeminal nerve, or cause symptoms similar to those of trigeminal neuralgia, including:
  • Tumours, such as posterior fossa tumours, extracranial masses along the trigeminal nerve, perineural spread of existing malignancy, cavernous sinus masses.
  • Multiple sclerosis.
  • Epidermoid, dermoid, or arachnoid cysts.
  • Aneurysm, or arteriovenous malformation.
• Management:
  • If there are no red flag symptoms and signs, offer the person carbamazepine. Start at 100 mg up to twice daily, and titrate in steps of 100 - 200 mg every two weeks, until pain is relieved.
  • If carbamazepine is contraindicated, ineffective, or not tolerated, seek specialist advice. Do not offer any other drug treatment unless advised to do so by a specialist.