Trigeminal autonomic cephalalgias (TACs) are a group of primary headache syndromes characterised by two main clinical characteristics: pain and oculofacial autonomic phenomena. Three headache forms are grouped as TACs: cluster headache (CH), paroxysmal hemicrania (PH) and short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT). These are distinguished mainly on the basis of attack duration. It lasts from 15 to 180 min in CH, from 2 to 30 min in PH and from 5 to 240 s in SUNCT. The most effective drug preventative in PH is indomethacin even if in few cases other non-steroidal anti-inflammatory drugs have been reported to be effective. SUNCT is commonly described as drug resistant. Recent studies report that lamotrigin may be the drug of choice for SUNCT.