what is a thunderclap headache
By Mayo Clinic Staff. Thunderclap headaches live up to their name, grabbing your attention like a clap of thunder. The pain of these sudden, severe headaches peaks within 60 seconds and can start fading after an hour. Some thunderclap headaches, however, can last for more than a week. Thunderclap headaches are often a warning sign of potentially life-threatening conditions, usually linked to bleeding in and around the brain. That's why it's so important to seek emergency medical attention if you experience a thunderclap headache.