19th June 2023

Diagnosis

Cluster headache is a primary headache disorder characterised by:

• Severe unilateral periorbital pain
• Ipsilateral autonomic symptoms such as conjunctival injection, lacrimation, eyelid oedema, nasal congestion, rhinorrhoea, forehead and facial flushing or sweating
• Typically symptoms last < 3 hours

As the name suggests, these headaches present as clusters, occurring in series lasting for a period (weeks or months) separated by intervals of remission. The different classifications of cluster headaches are based on their frequency:

• Episodic – occur in periods lasting 7 days to 1 year with pain-free intervals of at least 1 month.

• Chronic – occurs in periods for more than 1 year without being pain free or with periods of pain free intervals of less than 1 month.

Clinical features

• Unilateral periorbital pain with autonomic symptoms as described above
• Attacks last 15 min – 3 hours
• Attacks of headache may show circadian periodicity
• Males are affected four times more than females. Age group 20-40 years.