You probably know someone who gets short dizzy spells. Maybe you have had them yourself.
A brief whirl when you roll over in bed, or a wave when you tip your head back to look at a shelf. For most people it fades. Then, months later, it comes back.
About half of patients treated for the most common form of vertigo see it return within a year, according to Mayo Clinic.
The culprit is almost always a condition called benign paroxysmal positional vertigo, or BPPV.
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It is the most common cause of recurring dizziness, and one of the easiest to treat.
Vertigo is not the same as feeling faint. It is a specific sensation of spinning or movement, as if the room is sliding around you. Dizziness, by contrast, is lightheadedness or loss of balance.
The distinction matters, because the causes and the treatments are very different.
What causes BPPV and why it keeps returning
Inside each inner ear sit tiny calcium carbonate crystals that help the body sense gravity. When some break loose and drift into one of the balance canals, they trigger a short spinning sensation every time the head moves a certain way.
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Lying down, rolling over, or tipping the head back is often enough to set off an attack lasting less than a minute. Neil Shepard, an audiologist at Mayo Clinic, says head trauma is one common way the crystals get knocked loose in the first place.
BPPV is by far the most common vestibular disorder. According to the American Academy of Otolaryngology-Head and Neck Surgery, between 17 and 42 percent of patients with vertigo end up with a BPPV diagnosis.
It is especially common in older adults, where it also contributes to falls, depression and limits on daily activity. 86 percent of people with BPPV report some disruption to their daily life, the academy says.
Why does it come back? Repositioning moves the crystals out of the canal, but it does not stop new ones from loosening later. Head trauma, infections, or simple aging can start the process again.
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The lifetime risk of BPPV reaches about 2.4 percent of the general population, with women affected more often than men, according to a review on StatPearls from the National Library of Medicine.
Episodes most often first appear between the ages of 40 and 70.
The simple maneuver that still works best
For posterior canal BPPV, the standard treatment is a short sequence of head and body positions known as the Epley maneuver, or canalith repositioning procedure.
The clinician guides the patient through three or four positions. The movements use gravity to roll the crystals back where they belong, usually in a single office visit.
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The AAO-HNS guideline is unusually firm on this point. Repositioning is a strong recommendation. Routine use of vestibular suppressant medications such as antihistamines and benzodiazepines is specifically advised against.
Older advice that required patients to sleep upright or avoid certain positions for several nights afterward has also been dropped.
Doctors confirm BPPV with the Dix-Hallpike test. The patient is tilted into a specific head-down position while the clinician watches for a telltale pattern of involuntary eye movements.
If those appear, the diagnosis is clear and treatment can happen in the same visit.
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Two other inner-ear conditions can also produce recurring vertigo. Vestibular neuritis and labyrinthitis follow an infection and tend to cause longer, continuous episodes rather than brief spinning attacks.
Meniere's disease is a rarer inner-ear disorder. Its attacks last from 20 minutes to several hours, often with hearing loss, ringing in the ear, and a feeling of fullness.
Anyone who has had more than one episode of vertigo should see a doctor rather than wait it out. The test, the treatment, and the follow-up usually fit into a single clinic visit. Over-the-counter dizziness pills will not fix the underlying problem.
This article is made and published by Ida-Marie Palm Varbæk, who may have used AI in the preparation.