Headache in Primary Care
Headache is one of the most common presenting complaints in primary care, with tension-type headache and migraine accounting for the vast majority of cases. A structured approach to history and red flag identification is essential to exclude sinister pathology.
Key Facts
Tension-type headache is the most common primary headache, affecting up to 80% of the population at some point Migraine affects approximately 15% of adults in the UK, with a 3:1 female-to-male ratio NICE CKS recommends a structured history focusing on onset, character, frequency, duration, and associated features Red flags (SNOOP): Systemic symptoms, Neurological signs, Onset sudden (thunderclap), Older age (>50 new headache), Pattern change Medication overuse headache should be suspected when analgesics are used on ≥15 days/month for simple analgesics or ≥10 days/month for triptans/opioids Thunderclap headache (peak severity within 5 minutes) requires urgent investigation to exclude subarachnoid haemorrhage Giant cell arteritis should be considered in all patients >50 years with new-onset headache (NICE NG100) Headache diary for ≥8 weeks is recommended to establish diagnosis and identify triggers
Overview
Key Facts
Headache accounts for approximately 4% of all GP consultations. The vast majority are primary headaches (tension-type, migraine, cluster), but a systematic approach is required to identify the small proportion with secondary causes requiring urgent investigation or referral.
Epidemiology
- Tension-type headache: lifetime prevalence 60-80%
- Migraine: affects 15% of UK adults; 6% of men and 18% of women
- Cluster headache: prevalence 0.1%; male-to-female ratio 3:1
- Medication overuse headache affects approximately 1-2% of the general population
- Headache is the most common neurological reason for GP consultation
Aetiology
- Primary headaches: tension-type (peripheral and central sensitisation), migraine (cortical spreading depression, trigeminovascular activation), cluster (hypothalamic dysfunction)
- Secondary headaches: medication overuse, intracranial pathology (tumour, haemorrhage, infection), giant cell arteritis, idiopathic intracranial hypertension, cervicogenic headache
- Triggers: stress, sleep disturbance, hormonal changes (menstruation), dietary factors (alcohol, caffeine withdrawal, cheese), environmental factors
Pathophysiology
- Tension-type: peripheral myofascial nociception with central sensitisation in chronic forms
- Migraine: cortical spreading depression triggers trigeminovascular system activation, leading to release of CGRP and vasoactive peptides causing neurogenic inflammation
- Cluster: hypothalamic activation with parasympathetic outflow via the trigeminal-autonomic reflex
- Medication overuse: chronic analgesic use causes downregulation of endogenous pain-modulating pathways and central sensitisation
Clinical Presentation
Tension-Type Headache
- Bilateral, pressing or tightening quality ('band-like')
- Mild to moderate intensity
- Not aggravated by routine physical activity
- No nausea or vomiting (mild photophobia OR phonophobia may be present but not both)
- Duration: 30 minutes to 7 days
Migraine
- Unilateral (60%), pulsating/throbbing quality
- Moderate to severe intensity
- Aggravated by routine physical activity
- Associated nausea/vomiting, photophobia, and phonophobia
- Duration: 4-72 hours
- With aura in 25%: visual (scotomata, fortification spectra), sensory, speech disturbance lasting 5-60 minutes
Cluster Headache
- Strictly unilateral, severe periorbital/temporal pain
- Associated ipsilateral autonomic features: lacrimation, conjunctival injection, rhinorrhoea, ptosis, miosis
- Duration: 15-180 minutes
- Frequency: 1-8 attacks per day in bouts lasting 6-12 weeks
Medication Overuse Headache
- Present on ≥15 days/month
- Develops or worsens during regular overuse of analgesics
- Typically bilateral, dull, worse on waking
Red Flags
- Thunderclap headache (maximal intensity within 5 minutes) — subarachnoid haemorrhage
- New headache in patient >50 years — giant cell arteritis, intracranial pathology
- Progressive headache with focal neurological signs — space-occupying lesion
- Headache with papilloedema — raised intracranial pressure
- Headache with fever, neck stiffness, rash — meningitis
- Headache worse on coughing/straining/lying flat — raised ICP
- New headache in immunocompromised or cancer patients
Differential Diagnosis
| Diagnosis | Key Features | Investigation |
|---|---|---|
| Tension-type headache | Bilateral, pressing, mild-moderate, no nausea | Clinical diagnosis, headache diary |
| Migraine | Unilateral, pulsating, nausea, photophobia | Clinical diagnosis (ICHD-3 criteria) |
| Cluster headache | Severe periorbital, autonomic features, circadian pattern | Clinical; MRI brain to exclude secondary cause |
| Medication overuse headache | ≥15 days/month, analgesic use ≥10-15 days/month | Headache diary, medication review |
| Subarachnoid haemorrhage | Thunderclap onset, worst headache of life | CT head (within 6h), LP if CT negative |
| Giant cell arteritis | Age >50, scalp tenderness, jaw claudication, raised ESR | ESR, CRP, temporal artery biopsy |
| Idiopathic intracranial hypertension | Obese young woman, papilloedema, visual obscurations | MRI/MRV, LP with opening pressure |
| Brain tumour | Progressive, worse on waking, focal neurology | MRI brain with contrast |
Diagnosis / Investigation
Bedside
- Blood pressure measurement
- Fundoscopy (papilloedema screening)
- Neurological examination including cranial nerves
- Temporal artery palpation in patients >50 years
- Visual acuity assessment
Bloods
- ESR and CRP: if giant cell arteritis suspected (ESR often >50 mm/hr)
- FBC: if systemic symptoms
- U&Es, TFTs: if secondary causes considered
Imaging
- CT head: urgent if thunderclap headache, acute neurological deficit
- MRI brain: if red flags present, progressive headache, new neurological signs, suspected space-occupying lesion
- CT/MR angiography: if subarachnoid haemorrhage or cerebral venous sinus thrombosis suspected
Special Tests
- Lumbar puncture: if CT negative but SAH suspected (xanthochromia); for measuring opening pressure in suspected IIH
- Temporal artery biopsy: if GCA suspected
- Headache diary: minimum 8 weeks, documenting frequency, duration, triggers, medication use
Management
Non-pharmacological
- Reassurance and patient education about primary headache diagnosis
- Headache diary to identify and avoid triggers
- Regular sleep pattern, adequate hydration, regular meals
- Stress management techniques (CBT, relaxation therapy, mindfulness)
- Limit caffeine intake; address screen time and posture
- For medication overuse headache: abrupt withdrawal of overused analgesic (except opioids/barbiturates — gradual taper)
Pharmacological
Acute treatment — Tension-type headache:
- Paracetamol 1g QDS or ibuprofen 400mg TDS (first-line)
- Aspirin 900mg as alternative
- Avoid codeine-containing preparations (risk of medication overuse)
Acute treatment — Migraine:
- Oral triptan (sumatriptan 50-100mg) + NSAID (naproxen 500mg) or + paracetamol 1g (NICE CKS)
- Sumatriptan 50mg is available OTC
- Anti-emetic if needed: metoclopramide 10mg or prochlorperazine 10mg buccal
- Avoid opioids
Prophylaxis — Migraine (if ≥4 attacks/month or significantly disabling):
- Propranolol 40-240mg daily (first-line; NICE CKS)
- Topiramate 25-100mg daily (contraindicated in pregnancy — teratogenic)
- Amitriptyline 10-75mg nocte (off-label; also useful if coexistent tension-type)
- Candesartan 8-16mg daily (off-label alternative)
- CGRP monoclonal antibodies (erenumab, fremanezumab, galcanezumab) — NICE TA for episodic/chronic migraine after ≥3 preventive failures
Cluster headache:
- Acute: sumatriptan 6mg SC or high-flow oxygen 12-15 L/min via non-rebreather mask for 15-20 minutes
- Prophylaxis: verapamil 240-960mg daily (first-line, requires ECG monitoring); short course prednisolone 60-100mg tapering
Surgical
- Occipital nerve stimulation for refractory chronic cluster headache (specialist centres)
- Greater occipital nerve block with local anaesthetic ± corticosteroid for refractory cases
Referral Criteria
- Red flag features: urgent/2-week-wait referral as appropriate
- Suspected cluster headache: refer to neurologist
- Migraine refractory to ≥2 prophylactic agents: refer to headache specialist
- Suspected medication overuse headache not responding to withdrawal: neurology referral
- Diagnostic uncertainty or atypical features
Prognosis
- Tension-type headache: chronic form (≥15 days/month) develops in 2-3% of episodic sufferers
- Migraine: improves in 60-70% of women after menopause; remission rates of 40% over 10 years
- Cluster headache: episodic form may become chronic in 10-15%; spontaneous remission in 10-20%
- Medication overuse headache: 50-70% improve within 2 months of withdrawal; relapse rate 30-45% at 1 year
- Secondary headache prognosis depends on underlying cause
- Migraine with aura carries a small increased risk of ischaemic stroke, particularly in women using combined hormonal contraception
Other Relevant Information
ICHD-3 Migraine Without Aura Criteria
| Criterion | Requirement |
|---|---|
| A | ≥5 attacks fulfilling criteria B-D |
| B | Duration 4-72 hours |
| C | ≥2 of: unilateral, pulsating, moderate-severe, aggravated by activity |
| D | ≥1 of: nausea/vomiting, photophobia AND phonophobia |
Headache Red Flags (SNOOP Mnemonic)
| Letter | Feature | Concern |
|---|---|---|
| S | Systemic symptoms (fever, weight loss, cancer, HIV) | Secondary cause |
| N | Neurological signs or symptoms | Space-occupying lesion, vascular |
| O | Onset sudden (thunderclap) | SAH, CVST, dissection |
| O | Older age (>50 new headache) | GCA, malignancy |
| P | Pattern change or progressive | Secondary cause |