Most cases of vertigo—dizziness so severe it makes you feel like the room is spinning—last for a few days at most. It can also recur periodically, a condition known as benign positional vertigo. The problem usually stems from tiny particles that get stuck in a sensitive area of the inner ear that’s responsible for maintaining balance.
Many sufferers get immediate relief from a series of repositioning movements, called the Epley maneuver, that can dislodge the particles. You can learn the exercises in a doctor’s office or on your own on the American Academy of Family Physician's web site (search for “Epley maneuver”). If your vertigo has lasted longer than a week, ask your doctor about other possible causes, including multiple sclerosis, stroke, or more rarely, a brain tumor.