Source of Support: None, Conflict of Interest: None
Some headaches are relatively uncommon. They may be either primary of secondary and their recognition is dependent on the characterization of symptoms as well as identification of certain specific situations in which they need to be considered in the differential diagnosis. Primary headache syndromes like the paroxysmal hemicranias, SUNCT (short-lasting unilateral neuralgiform headache with conjunctival injection and tearing), cough headaches and hypnic headaches are uncommonly encountered in routine clinical practice. They have subtle unique features and specific therapies which differentiate them from the commoner primary headaches. Among the secondary causes, headaches may be an uncommon presenting feature of known clinical disorders, lack of awareness of which may result in significant morbidity. These disorders which may present with headache as the main symptom will be the focus of discussion in this review.