An epidural hematoma is a fast-growing blood clot between the skull and the outer brain lining. It usually follows a direct blow to the head that may seem minor at first, so early clues are easy to miss. The classic start is a brief blackout, followed by a “lucid interval.” The person wakes up, talks normally, then drifts downhill again within minutes to hours. Headache ramps up quickly. It feels like a drum pounding on one side and gets worse with every heartbeat. Nausea and vomiting come on fast, often with little warning. The sick feeling does not ease after... Learn more