A sharp, intense headache that hits out of nowhere — then disappears seconds later — is one of the most alarming sensations patients describe. And yes, it feels scary. But in most cases, headaches that last only a few seconds are not caused by tumors, bleeding, or strokes. What I see most often: • brief nerve irritation in the scalp or face • muscle or cervical spine tension sending pain upward • primary stabbing headaches (short, benign nerve misfires) • sudden changes in blood vessel tone The