It is one of the most common medical problems associated with traveling. It can strike in the middle of an airplane ride, a roller-coaster ride, a cruise, even the briefest car trip.
It is motion sickness. And whether it's just a slight queasiness or a gut-wrenching bout of nausea and vomiting, it can ruin a trip.
Creative and physically fit people are among the most likely victims, two recent research studies suggest. But a local expert, Dr. Fred Linthicum, a researcher at the House Ear Institute, believes more research is needed.
It is difficult to predict who will suffer motion sickness, he said, and hard to say which mode of transportation will cause the upset. People who get airsick don't necessarily get carsick, he said, and vice versa. "Different motions affect people differently. We don't know why."
There are two theories currently enjoying popularity among motion sickness researchers, said Linthicum. According to one theory, the nervous system becomes overloaded with signals traveling simultaneously to the eyes and the ears. Another theory suggests that the brain's balance centers are close to the areas of the brain that receive vomit-reflex messages and the signals just get mixed up.
"This last (theory) is more recent and makes the most sense to me," Linthicum said, "but it is still not proven."
The afflicted are, understandably, more interested in prevention and remedies than causes. For help, Linthicum suggests over-the-counter medications like Dramamine. Or ask your doctor to prescribe a scopolamine patch, which can be placed behind the ear several hours before you embark.
"Be sure not to use two patches," Linthicum warned, noting that many people overdose themselves with the patch. The patch can cause its own discomforts, he said. "It can blur the vision and give you a dry mouth."
Low on Linthicum's list of preferred treatments is a wrist band designed to stimulate the acupressure point some believe is associated with nausea. "There's never been a controlled study (to prove) that this works," he said.
Once you are on board ship, in a car or on a plane, try lying down and closing your eyes, said Linthicum. Travelers prone to motion sickness should not read while in motion, according to the American Academy of Otolaryngology--Head and Neck Surgery. And don't sit in a seat that faces backward, says the academy. Queasy riders should also avoid strong odors and spicy foods before setting out on a trip.
The motion-sick may take comfort in Linthicum's belief that the affliction is not psychologically based. "It's definitely not all in the head."
For more information on motion sickness remedies, send a self-addressed, stamped envelope to the American Academy of Otolaryngology--Head and Neck Surgery, 1 Prince St., Alexandria, Va. 22314.