Headache - Cluster

Related Subjects:Migraine |Basilar Migraine |Cluster Headaches |Sumatriptan |Tension Headache |Analgesic Overuse Headache |Headaches in General |Neurological History taking |Trigeminal Neuralgia |Thunderclap Headache |Subarachnoid Haemorrhage |Perimesencephalic Subarachnoid haemorrhage

🔥 Cluster Headaches are among the most painful primary headache disorders. They often earn the nickname "suicide headaches" due to their intensity. ⏰ They typically follow circadian rhythms, often waking patients at night, and occur in clusters lasting weeks to months.

🧾 About

• Definition: Severe, unilateral, episodic headaches occurring in "clusters" over several weeks, separated by headache-free periods.
• Pattern: Attacks occur daily (sometimes multiple times per day), then remit for months before recurring.

🧬 Aetiology

• Pathophysiology: Thought to involve hypothalamic dysfunction with abnormal circadian regulation and trigeminal autonomic reflex activation.
• May be triggered by alcohol, nitroglycerin, or strong odours during an active cluster phase 🍷.

🩺 Clinical Presentation

• Headache Characteristics: Excruciating unilateral pain, typically orbital, supraorbital, or temporal. Duration: 15–180 minutes.
• Population: 3–4 times more common in men, usually starting between ages 20–50.
• Autonomic Features (ipsilateral):
  • Conjunctival injection, lacrimation 😢
  • Nasal congestion or rhinorrhoea 🤧
  • Eyelid oedema, ptosis, miosis 😵
  • Facial sweating, flushing
• Behavioural clue: Patients are restless or agitated (unlike migraine where patients lie still).

📋 Diagnostic Criteria (ICHD-3)

• At least 5 attacks fulfilling the following:
• Severe unilateral orbital/supraorbital/temporal pain lasting 15–180 min.
• At least 1 ipsilateral autonomic feature (lacrimation, rhinorrhoea, eyelid oedema, facial sweating, miosis, ptosis).
• Frequency: 1 every other day up to 8 per day.

🔍 Investigations

• Clinical diagnosis: No specific test required.
• MRI/CT: Performed if atypical features or secondary pathology (e.g. pituitary lesion, carotid dissection) suspected.

⚖️ Differential Diagnosis

• Migraine: Longer, throbbing, often with photophobia/phonophobia.
• Orbital pathology: e.g. glaucoma, orbital cellulitis, cavernous sinus thrombosis.
• Carotid dissection: Headache + Horner’s syndrome ⚠️.
• Subarachnoid haemorrhage: Sudden thunderclap onset.
• Trigeminal neuralgia: Short electric-shock pains, triggered by touch.

🚑 Acute Management

• High-flow Oxygen: 100% O₂ via non-rebreather at 12–15 L/min for 15–20 min (first-line; rapid relief in many).
• Triptans (non-oral only):
  • Sumatriptan SC injection (6 mg) – gold standard 💉.
  • Sumatriptan intranasal (10–20 mg) or Zolmitriptan nasal spray (5 mg).
• Avoid oral triptans: Onset too slow for cluster attacks.

🛡️ Prevention

• Verapamil: First-line. Start at 80 mg TDS, titrate every 2 weeks up to 960 mg/day. Requires ECG monitoring for PR prolongation ❤️.
• Lithium: Alternative if verapamil contraindicated. Monitor renal + thyroid function.
• Steroids: Prednisolone 60 mg tapered over 2–3 weeks as a bridging option.
• Melatonin: 9–12 mg nocte may reduce nocturnal attacks 🌙.
• Greater Occipital Nerve Block: Local anaesthetic ± steroid injection, effective bridge until oral prophylaxis works.
• Neuromodulation: gammaCore® (vagus nerve stimulator) approved by NICE in refractory cases.

📌 Exam Pearls

✅ Middle-aged man, recurrent unilateral orbital pain with tearing + agitation = think cluster headache.
✅ Responds dramatically to O₂ and subcutaneous sumatriptan.
✅ Restlessness differentiates from migraine (migraineurs prefer lying still).

📚 References

• NICE CKS – Cluster headache
• Hull NHS Headache Guidelines

Cases - Cluster Headache

• Case 1 - Nocturnal Attacks: A 36-year-old man describes severe unilateral periorbital pain waking him at night, lasting 45 minutes. Attacks occur daily for 2 weeks, then remit. Exam during attack: conjunctival injection, lacrimation, ptosis on the painful side. Diagnosis: Cluster headache (episodic). Management: Acute: high-flow O₂, subcutaneous sumatriptan. Preventive: verapamil.
• Case 2 - Alcohol Trigger: A 42-year-old man develops excruciating stabbing pain behind his left eye 20 minutes after drinking beer. He is agitated, paces around, and has ipsilateral rhinorrhoea. Attacks have recurred at the same time each evening for the past month. Diagnosis: Cluster headache precipitated by alcohol. Management: Avoid alcohol during cluster period; acute therapy with 100% O₂; preventive verapamil with ECG monitoring.
• Case 3 - Chronic Cluster Headache: A 50-year-old man reports continuous cycles of daily unilateral orbital headaches for the past year, with no remission >3 months. Attacks last 60–90 minutes, associated with lacrimation and nasal congestion. Diagnosis: Chronic cluster headache. Management: Acute: subcutaneous or intranasal triptan; O₂. Preventive: high-dose verapamil (with ECG), lithium if refractory. Neurology referral.

Teaching Commentary 💥

Cluster headache is a trigeminal autonomic cephalalgia, characterised by: - Excruciating, strictly unilateral orbital/temporal pain, - Short duration (15–180 min), - Occurs in “clusters” (weeks–months), often nocturnal, - Associated with ipsilateral autonomic features (lacrimation, rhinorrhoea, ptosis, conjunctival injection). Typical patient = middle-aged man, smoker, restless during attacks. Acute treatment: high-flow oxygen, subcutaneous or intranasal triptans. Preventive: verapamil (first-line), lithium, topiramate. Alcohol is a classic trigger during active clusters.