For Katy Breuer, the symptoms start as soon as she steps off a cruise ship. She feels dizzy and disoriented, can’t eat and can’t find her land legs. “It’s debilitating,” says Breuer, an executive coach from Vienna, Va.

It could be worse. For some travelers, the rocking never ends. They suffer from mal de debarquement syndrome (MdDS), a rare and chronic form of reverse motion sickness. Instead of getting seasick on board, their illness begins when they hit dry land — and it never ends.

Mal de debarquement syndrome — “disembarkation sickness” — is one of the least understood travel disorders. It’s also a topic of intense curiosity, particularly as travelers begin planning next year’s cruises.

“Mal de debarquement is a rare neurological condition described by some people as a continuous perception of self-motion and imbalance,” says Radhika Vij, director of international travel health services at MedStar Union Memorial Hospital in Baltimore.

Not everyone is as lucky as Breuer, whose illness was transient. Marilyn Josselyn got full-blown MdDS after a riverboat cruise in Russia in 1998. She had to quit her job as a court reporter because she couldn’t maintain her balance.

“I’ve been rocking ever since,” says Josselyn, who lives in Audubon, Pa.

Josselyn is working to raise awareness of her condition. She helped start the MdDS Foundation, a nonprofit organization that seeks treatments and a cure for MdDS. The organization maintains a private Facebook support group with more than 4,000 members and publishes a list of physicians who treat MdDS.

“There’s an extreme difference between MdDS and not being able to find your land legs,” she says. “MdDS can last years and years.”

Common symptoms of mal de debarquement include the feeling of rocking, swaying or bobbing, lasting several weeks or more. Patients have complained of MdDS after roller coasters, flight-simulator sessions — even sleeping on water beds. Anyone can get mal de debarquement, but women between ages 30 and 60 are most susceptible, experts say.

What causes mal de debarquement? Research suggests the problem doesn’t originate in the inner ear, which regulates balance, but in the brain.

“After a while, the brain adjusts to these new types of movements and in some instances is unable to readapt to its baseline patterns once the movement has stopped,” Vij says.

In the vast majority of cases, the symptoms of land sickness last only a few days. Heather Sykes took her first cruise last year to celebrate her 40th birthday. She knew she was susceptible to motion sickness, so she wore a scopolamine patch during the eight-day Western Caribbean trip.

“I didn’t experience seasickness during the cruise,” says Sykes, a program manager with the federal government who lives in Alexandria, Va. “But when I disembarked and took off the patch, I developed symptoms that were similar to a bad hangover, even though I had not had any alcohol and was well hydrated. The room was spinning, I was nauseous, and I was completely unable to focus on a computer or TV screen.” It took five days for her symptoms to abate.

“I will not go on a cruise again,” she says.

Although travelers most often experience these symptoms after cruises, doctors say, they can occur after any long journey. Consider what happened to Meredith Kulikowski, a government contractor from Laurel, Md. She took the auto train, round trip, from Lorton, Va., to Sanford, Fla.

“I was okay going down,” she remembers. “But I felt awful when I arrived in Virginia.”

Once her feet were back on solid ground, she says, she felt seasick and hung over.

“My equilibrium was off, and I just felt nauseous the whole time,” she says. “The symptoms lasted for about a week.”

Because land sickness is something of a mystery, there’s little agreement on prevention. Some medical experts told me you might avoid the ailment by taking the same steps you do to prevent motion sickness. Those include avoiding heavy meals and alcohol and — for brief boat rides — focusing on a fixed object in the distance during your journey.

Doctors may prescribe anti-seizure medications or antidepressants to treat mal de debarquement. But they’ll probably start your treatment by suggesting you reduce stressors in your life. Transcranial magnetic stimulation, a type of therapy that stimulates the brain with magnetic fields, and a therapy called readaptation of the vestibulo-ocular reflex, which helps your eyes adjust to being on land, are among the treatment options being explored. But they have not been thoroughly tested, according to the MdDS Foundation.

“It is a hard condition to treat, and options are limited,” says Vij, the Baltimore physician. “No one thing works for all.”

Some of the patients I interviewed about motion sickness on land said their post-cruise symptoms didn’t come as a surprise. They knew they were prone to motion sickness and weren’t shocked to feel as if they were still on the ship after making landfall.

Rick Orford, a frequent cruiser, says he experiences symptoms whenever he steps off a boat. “My legs feel wobbly. It’s as if I can still feel the sway of the ship,” he says.

Orford’s partner, Andrea Spallanzani, is a general surgeon in Italy. He’s watched Orford suffer from this little-known travel malaise and chronicled their adventures on a blog called Travel Addicts. A little exercise and antidepressants can lessen the symptoms of mal de debarquement, he says. “But there is no cure.”

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