An airplane headache (AH) is a specific type of pain primarily felt in the fronto-orbital region, which is the area around the forehead and eyes. It is usually a sharp, stabbing, or jabbing sensation that occurs almost exclusively on one side of the head (unilateral). Most sufferers experience the onset during the landing phase—though it can occur during takeoff—as the cabin pressure rapidly changes. The pain is intense but typically short-lived, usually lasting about 20 to 30 minutes before subsiding. It is thought to be caused by barotrauma to the sinuses, where the pressure difference between the sinuses and the cabin leads to the sudden stretching of nerve endings. If the pain persists longer than an hour or occurs during the middle of the cruise phase without pressure changes, it may be a different type of headache altogether, such as a migraine triggered by dehydration or altitude changes.