Post Traumatic Headache

Post traumatic headache is a secondary headache that begins within 7 days of head injury, regaining consciousness after the injury, or discontinuing medicines that impair recognition of headache after injury. It is called acute if it resolves within 3 months and persistent if it continues beyond 3 months.

• Most common sequel of mild traumatic brain injury (concussion); up to 30 to 60 percent of patients report headache in the first weeks, and 15 to 25 percent still have headache at 12 months.
• Headache severity does not correlate with injury severity: mild injury often produces more persistent headache.
• Phenotype: migraine like (most common, about 40 to 50 percent), tension-type-like, cervicogenic, or mixed; sometimes with cluster like or neuralgic features.
• Risk factors: female sex, pre-existing migraine, anxiety, depression, post-traumatic stress, litigation or compensation, prior concussion, and overuse of analgesics.
• Mechanisms include axonal injury, neuroinflammation, cervical soft tissue injury, and CGRP-related mechanisms.

• Headache from within hours to 7 days of injury; may be daily, with episodic migraine like flares.
• Associated post-concussion symptoms: dizziness, poor concentration, memory difficulty, irritability, fatigue, sleep disturbance, photophobia, phonophobia, tinnitus, anxiety and depression.
• Neck pain and reduced range of motion may indicate a cervical component.
• Examination: general neurological examination, cranial nerves, fundi, gait and balance, neck, and skull for tenderness or deformity.
• Warning features requiring urgent evaluation: worsening headache, repeated vomiting, drowsiness, confusion, seizures, focal deficit, pupil asymmetry, clear fluid from nose or ear, bruising behind the ear or around the eyes, and new neck pain with neurological change.

• Clinical, using the timing of onset and the exclusion of other causes.
• CT head urgently in adults after head injury if any of: Glasgow Coma Scale under 13 at any time, or under 15 at 2 hours; suspected open or depressed skull fracture or basal skull fracture sign; post-traumatic seizure; focal deficit; more than 1 episode of vomiting; amnesia for over 30 minutes before impact; age 65 or over with loss of consciousness or amnesia; dangerous mechanism; anticoagulant use (CT within 8 hours).
• For delayed or persistent headache: CT or MRI for worsening headache, new neurological signs, or suspected subdural haematoma, particularly in older adults and anticoagulated patients, in whom subdural haematoma can appear weeks later; MRI for suspected venous sinus thrombosis, carotid or vertebral dissection (CT or MR angiography), cerebrospinal fluid leak (orthostatic headache), or intracranial hypotension.
• Assess for depression, anxiety, post-traumatic stress, sleep disorder, and substance and analgesic overuse.
• Differentials: subdural or extradural haematoma, post-traumatic hydrocephalus, cervical artery dissection, CSF leak, post-concussion syndrome, pre-existing migraine, medication overuse headache.

Acute phase (first 2 weeks)

• Short relative rest for 24 to 48 hours, then graded return to cognitive and physical activity with symptom limited progression; avoid prolonged rest.
• Analgesia: paracetamol 1 g orally up to four times daily (maximum 4 g), or ibuprofen 400 mg three times daily with food, restricted to no more than 2 to 3 days a week after the first fortnight. Avoid NSAIDs in the first 24 to 48 hours if intracranial haemorrhage has not been excluded, and avoid opioids.
• Antiemetic for nausea: ondansetron 4 mg orally or metoclopramide 10 mg three times daily for up to 5 days.
• Sleep hygiene, hydration, regular meals and caffeine limitation.

Persistent headache: treat by phenotype

• Migraine like: sumatriptan 50 to 100 mg orally at onset (repeat after 2 hours, maximum 300 mg daily) or rizatriptan 10 mg; add NSAID. Preventives: amitriptyline 10 mg at night increasing to 50 mg, propranolol modified release 80 to 160 mg daily, topiramate 25 mg at night increasing to 50 mg twice daily, or candesartan 8 to 16 mg daily. Allow 8 to 12 weeks.
• Tension-type-like: amitriptyline 10 mg at night increasing by 10 mg weekly to 50 mg; physiotherapy and relaxation.
• Cervicogenic: physiotherapy and greater occipital nerve block with lidocaine 2 percent 2 mL and methylprednisolone 40 to 80 mg.
• Neuralgic features: gabapentin 300 mg at night increasing to 300 to 600 mg three times daily.
• Onabotulinumtoxin A for persistent chronic migraine phenotype under specialist care.
• Avoid opioids, benzodiazepines and butalbital containing products.

Rehabilitation and psychological care

• Cognitive behavioural therapy for chronic headache and post-concussion symptoms; vestibular and cervical rehabilitation for dizziness and neck pain; graded aerobic exercise under supervision when resting heart rate allows.
• Treat depression and sleep disorder; sertraline 50 mg daily (increase to 100 mg after 4 weeks if needed) or amitriptyline 10 to 50 mg at night may serve both mood and headache.
• Occupational and school adjustments; driving advice (do not drive until headache, dizziness and concentration allow safe driving).

Follow up

• Review at 2 weeks, then monthly; refer to a headache or brain injury service if headache persists beyond 3 months, if there are neurological findings, or if function is impaired.

Special groups

• Children and adolescents: paracetamol 15 mg/kg every 4 to 6 hours (maximum 75 mg/kg or 4 g daily, whichever is less) or ibuprofen 10 mg/kg three times daily (maximum 400 mg a dose); graded return to school; amitriptyline 0.25 mg/kg at night increasing to 1 mg/kg (maximum 50 mg), or propranolol 10 to 20 mg twice daily under specialist advice; avoid aspirin under 16 years.
• Older adults and anticoagulated patients: lower threshold for repeat CT because of delayed subdural haematoma; avoid NSAIDs.