Motion sickness often starts with an uncomfortable sensation of nausea or dizziness that can proceed to include headache, cold sweats, and vomiting. Experts believe it is triggered by a disturbance in the signals sent to the brain by the eyes and inner ear.

Although there are over-the-counter and prescription drugs to prevent motion sickness, they have some drawbacks. Nonprescription pills like Bonine or Dramamine can cause drowsiness.

The prescription patch Transderm Scop (scopolamine) can cause dry mouth, dizziness, drowsiness, and difficult urination.

One of the oldest motion sickness remedies we know of is ginger, which Chinese sailors and fishermen have relied on for centuries.

When it was tested against Dramamine a few decades ago, ginger was more helpful in preventing nausea in experimental subjects sitting in a spinning chair (The Lancet, March 20, 1982). More recent studies have provided mixed results (American Family Physician, June 1, 2007).

Ginger works best when it is taken at least half an hour before embarking on a plane, boat, or motor vehicle. It may be taken in capsules or as crystallized ginger (a delightful candy).

Some people prefer ginger ale. If you can find ginger ale that actually contains ginger — it has become rare in these days of artificial flavorings — a 12-ounce glass offers relief for a few hours.

“For travel sickness, I find ginger to be the best treatment. I buy capsules of ginger at a health food store and have taken them with me on ten cruises. Candied ginger is also useful for when it would be difficult to swallow capsules. It helps with sore throats too,” wrote a reader.

Another approach to managing motion sickness is with acupressure. But you don’t have to become an expert in this Oriental healing technique to benefit.

Just purchase Sea-Bands or a similar wristband with a plastic button designed to put pressure on the P6 acupressure point that relieves nausea.

In one study, women with a history of motion sickness took longer to feel nauseated in a rotating chair if they were wearing an acupressure wristband stimulating the P6 point than women in the control group without wristbands (Canadian Journal of Anaesthesia, Aug-Sep. 2005).

A different study, however, found no benefit from acupressure bands, whether or not the subjects were trained in their proper use (Aviation, Space, and Environmental Medicine, March 2004).

However, some of our readers say the devices have worked well: “I have used Sea-Bands for motion sickness and they are great. They go on your wrists and press on an acupressure point. This really helps me and I hope it will help others,” wrote one.

Sea-Bands are sold in pharmacies, airport gift shops, mail-order catalogs, and online.

The variable results in studies of these nondrug therapies for preventing motion sickness suggest that individual responses can be quite different, but there appear to be no side effects associated with them.

It may require some experimentation to find the most helpful approach for you.