There are two types of short-lasting unilateral neuralgiform headache attacks. They are differentiated by the specific symptoms they cause.
Short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT)
SUNCT attacks cause moderate to severe pain in one side of the head, in the area around the trigeminal nerve – around the eye, temple, or sometimes towards the back of the neck. The attacks last anywhere from a few seconds to ten minutes and based on the length of the attack it can be a single stab, a series of stabs or a saw tooth pattern of pain. People experience at least one attack per day, but might experience up to 200 attacks per day. SUNCT is associated with prominent redness and tearing of the eye on the side of the head pain and can also be accompanied by swollen or drooping eyelids, facial sweating, stuffy nose (nasal congestion) or a sense of fullness in the ear. As this is quite a rare condition, it’s not clear what causes SUNCT or how best to treat it – although it is thought that it could be related to a disorder of the hypothalamus, similar to cluster headaches.
Short-lasting unilateral neuralgiform headache attacks w/ cranial autonomic symptoms (SUNA)
SUNA is similar to SUNCT. It is differentiated by the associated symptoms. SUNA has no redness or tearing of the eye (or maybe only one of those symptoms) – instead, people experience the other cranial symptoms such as sweating, stuffy nose (nasal congestion), etc.
These headache types belong to a category of primary headache disorders called ‘trigeminal autonomic cephalalgias (TACs)‘.
Other trigeminal autonomic cephalalgias (TACs):