Thunderclap Headache: A Review of Different Aetiologies

Abstract

Thunderclap headache refers to a severe headache of abrupt onset. It is a neurological emergency with potentially catastrophic consequences and should therefore be recognized and investigated promptly. Several conditions may cause thunderclap headache. Subarachnoid haemorrhage remains the most common condition that needs to be ruled out in the first instance. When no cause is identified, the term primary thunderclap headache is used but this is a diagnosis of exclusion and should only be used after other conditions have been systematically ruled out with clinical evaluation and different imaging modalities. This review will discuss the clinically serious conditions to present as thunderclap headache that should be carefully considered.