1. What are the main types of headache?
Headache disorders are divided into two broad categories: primary headaches (see Key Terms below) — where the headache is the condition itself, with no underlying structural cause — and secondary headaches (see Key Terms below) — where the headache is a symptom of another condition. The vast majority of headaches encountered in primary care are primary.1
NICE CG150 — the UK clinical guideline for headache in people over 12 — identifies three principal primary headache disorders, plus a clinically important secondary pattern that frequently complicates them:1
Tension-type headache (TTH)
The most common headache disorder globally, affecting around 26% of the adult population at any given time.2 TTH is characterised by bilateral (both sides of the head), pressing or tightening pain — often described as a tight band around the head. It is mild to moderate in severity, is not aggravated by routine physical activity, and does not cause nausea or vomiting. Photophobia (see Key Terms below) or phonophobia (see Key Terms below) may be present, but not both together. Episodes last from 30 minutes to 7 days.1
TTH is classified as episodic (fewer than 15 headache days per month) or chronic (15 or more days per month). Simple analgesics — aspirin, ibuprofen, or paracetamol — are the recommended acute treatment. Triptans are not effective for TTH.1
Migraine
Covered in full in Article 22 of this series. In summary: migraine is unilateral (one side), pulsating, moderate to severe, aggravated by activity, and associated with nausea, photophobia, or phonophobia. It is the second most common primary headache type and the third highest cause of disability globally in adults under 50. Triptans are the primary migraine-specific acute treatment.1
Cluster headache
A rare but distinctively severe primary headache disorder, affecting approximately 0.1% of the population.1 Cluster headache belongs to a group called the trigeminal autonomic cephalalgias (TAC) (see Key Terms below). Attacks are characterised by severe to very severe unilateral periorbital (around the eye) or temporal (at the temple — the side of the head above the ear) pain — typically described as boring, stabbing, or burning — lasting 15 minutes to 3 hours and occurring up to 8 times daily. The defining clinical feature is the presence of ipsilateral (same-side) cranial autonomic symptoms: lacrimation (tearing), nasal congestion, rhinorrhoea (runny nose), ptosis (drooping eyelid), miosis (pupil constriction), or conjunctival redness (redness of the white of the eye). Restlessness or agitation during attacks is characteristic — unlike migraine, where patients typically lie still.1
Attacks occur in clusters — a period of frequent attacks lasting weeks to months — followed by a remission period that may last months or years. Some people develop chronic cluster headache without sustained remission.
Medication overuse headache (MOH)
A secondary headache pattern that develops when acute headache treatments are used too frequently. NICE CG150 estimates MOH affects 1–2% of the general population — making it among the most common causes of chronic daily headache.1 Using triptans, opioids, or ergotamine on 10 or more days per month, or simple analgesics on 15 or more days per month, is associated with MOH developing. The headache is typically daily or near-daily, often worse in the morning, and paradoxically worsens as more medication is taken. The recognised treatment is withdrawal of the overused drug — with an expectation that headache will initially worsen before improving.
🔑 Key terms
2. Why does it matter?
Headache is one of the most common reasons for GP consultations and neurological referral in the UK. The majority of headaches are primary — benign in the sense that they do not signal structural pathology — but they can cause significant disability, missed work, and reduced quality of life, particularly in people with frequent migraine or chronic TTH.
An important clinical and educational point is that the three main primary headache types require quite different management approaches. TTH does not respond to triptans; cluster headache requires acute treatment with oxygen or subcutaneous sumatriptan (Imigran), not oral analgesics; and migraine has its own evidence-based treatment pathway. Distinguishing the type accurately is therefore not academic — it has direct implications for what treatment is appropriate.
A further important point is that the vast majority of headaches, even in those presenting to their GP, are primary and do not signal serious underlying pathology. Brain tumour as a cause of isolated headache is substantially less common than many people fear.
📋 Clinical context: Fewer than 1 in 1,000 people under 50 presenting with an isolated headache will have a brain tumour — the presence of red flags (see below) is what appropriately drives investigation, not headache frequency or severity alone.5
3. What your doctor might discuss
Distinguishing the headache type
Diagnosis is clinical — based on history, using ICHD-3 criteria. The following features are the key distinguishing characteristics between the three main primary types:1
| Feature | Tension-type | Migraine | Cluster |
|---|---|---|---|
| Location | Bilateral (both sides) | Often unilateral | Unilateral periorbital (around the eye) |
| Character | Pressing, band-like | Pulsating, throbbing | Severe, boring or stabbing |
| Severity | Mild to moderate | Moderate to severe | Severe to very severe |
| Duration | 30 min – 7 days | 4 – 72 hours | 15 min – 3 hours |
| Nausea/vomiting | No | Yes | Variable |
| Autonomic features | No | No | Yes — same-side tearing, nasal congestion, ptosis |
| Activity effect | Not aggravated | Worsened | Agitated, pacing |
Treatment by type
- 1Tension-type headache (acute): aspirin, ibuprofen, or paracetamol. Triptans are not effective for TTH and should not be used. Frequent use of any analgesic risks progressing to medication overuse headache. For chronic TTH or frequent episodic TTH, preventive treatment with amitriptyline (Tryptizol) is considered.
- 2Migraine (acute): triptan + NSAID combination as first-line per NICE CG150, or simple analgesia with antiemetic at step one. See Article 22 of this series for full migraine management.
- 3Cluster headache (acute): 100% oxygen — 12–15 litres per minute for 15–20 minutes via non-rebreathable mask — or subcutaneous sumatriptan (Imigran) 6mg. Both carry strong evidence from randomised trials. Oral analgesics are not effective because cluster attacks are too brief for oral medications to be absorbed in time. Prevention: verapamil (Cordilox) is first-line.
- 4Medication overuse headache (MOH): withdrawal of the overused medication. Headache typically worsens in the first week before improving. Around half of those who withdraw successfully achieve a meaningful reduction in headache frequency at 2 months. NICE CG150 recommends abrupt withdrawal over gradual tapering for most cases.
Neuroimaging
NICE CG150 specifically advises not to refer people diagnosed with tension-type headache, migraine, cluster headache, or medication overuse headache for neuroimaging solely for reassurance. Neuroimaging in primary headache has a very low yield for structural pathology and may reinforce health anxiety without clinical benefit. Investigation is driven by red flags, not by headache frequency or severity alone.1
⚠️ Headache patterns clinically recognised as requiring prompt assessment
- Thunderclap headache (see Key Terms below) — severe onset reaching maximum intensity within seconds to minutes: clinically recognised as requiring urgent assessment to exclude subarachnoid haemorrhage (bleeding into the space around the brain), cervical artery dissection, and other acute vascular causes.
- New headache in someone over 50 — particularly progressive, associated with scalp tenderness, or jaw pain on chewing: warrants investigation to exclude giant cell arteritis (GCA — a vasculitic condition affecting arteries in older adults) and intracranial pathology.
- Headache with fever, neck stiffness, rash, or altered consciousness — clinically recognised as time-sensitive; 111 and urgent GP services exist for this presentation.
- New focal neurological deficit — weakness, speech difficulty, or visual loss not consistent with typical aura.
- Headache worsened by exertion, coughing, or straining (Valsalva) — may indicate raised intracranial pressure.
- Waking from sleep with headache that is progressive — a pattern requiring investigation.
- New headache in someone with known cancer, immunosuppression, or HIV.
4. What the research shows
5. Putting it all together
Headache is one of the most common presentations in medicine, and the great majority are primary — benign in origin, with no structural underlying pathology. The clinically important skill is accurate type identification, because tension-type headache, migraine, and cluster headache each require fundamentally different acute treatment approaches. Using triptans for tension-type headache is ineffective; using oral analgesics for cluster headache is too slow; misidentifying migraine as tension headache leaves a treatable condition undertreated.
Medication overuse headache is a common and often unrecognised complication of all three types — affecting an estimated 1–2% of the general population — and responds to withdrawal of the overused drug, though with an initial period of worsening. Red flag features — particularly thunderclap onset, new headache over 50, systemic features, and focal neurology — are the appropriate triggers for investigation, not headache frequency or severity alone.
Most headaches are primary, most are treatable, and most do not signal serious pathology — but accurate identification of the type is what makes effective treatment possible.