While you may be used to an occasional headache from stress or one too many drinks, certain types of headaches can be cause for more concern. The three most common—and not dangerous—types of headaches are tension, cluster, and migraines, but “there are a couple of characteristics we look for as emergency doctors that tip us off that a headache is more than the average headache,” explains Stanton.
Head to the ER if… the pain is intense and sudden. “Is it the worst headache of your life? Did it come on suddenly like you were struck by lightning or hit in the head with a hammer?” says Stanton. “These are the two major questions we will ask to gauge the risk for a potentially deadly cause of headache known as subarachnoid hemorrhage.” A headache is also worrisome if it is accompanied by a fever, neck pain, or stiffness and a rash, which could signal meningitis.