The Strange Reason You May Suddenly Feel Dizzy

—Silivonochka/Getty Images; Roc Canals—Getty Images If you’ve ever sat up quickly or rolled over in bed abruptly and felt like the room was spinning or whirling around you when you’re actually still, you may have experienced a condition called benign paroxysmal positional vertigo (BPPV) without knowing what it was.

This vestibular disorder—one that affects the inner ear —is one of the most common causes of vertigo, and it can make people feel very dizzy, unsteady , sweaty, even nauseous .

Individual bouts tend to be brief—usually lasting 15 to 60 seconds at a time—but they can recur with certain head movements, make it difficult to function, and increase the risk of falling.

“The term ‘benign’ is the first part of the phrase—it does not feel benign when you experience it,” says Dr.

Nedim Durakovic, an associate professor of otolaryngology and neurotology at the Washington University School of Medicine in St.

Louis.

Before the condition was well understood, “people thought that patients were having strokes when they had vertigo, [but] this is not the stroke form of vertigo.” Here’s what to know about BPPV.

What causes BPPV? With BPPV, tiny calcium carbonate crystals—called otoconia—that usually sit on hair cells in the inner ear get dislodged from where they belong and travel into one of the three semicircular canals of the inner ear.

A change in head position, such as while rolling over in bed or tipping your head back in the shower, is what usually triggers BPPV symptoms.

It’s natural for these crystals to be in the ear.

“They are part of your normal anatomy for your balance function,” says Dr.

Gail Ishiyama, a professor in the departments of neurology and head and neck surgery and director of the Vestibular Clinical Laboratory at the UCLA School of Medicine.

With BPPV, “they’re just in the wrong place, and that can cause vertigo.” BPPV affects twice as many women as men, and it’s particularly common between the ages of 40 and 70.

It can happen anytime, but head trauma or dental procedures involving drilling are two of the more common triggers, Ishiyama says.