There are many reasons some people hate to fly: a fear of heights, being assigned the dreaded middle seat, sitting next to a chatty passenger, and eating sub-par airplane food. But are you apprehensive about flying because of certain symptoms you develop during the flight? If so, don’t worry, you’re not alone.

Every year, more than 2 million people seek medical advice about motion sickness, a condition that affects up to half of airline passengers. That means air travel for many people could be uncomfortable, if not unbearable. What’s more, a recent survey of 1,001 adults conducted by Novartis Consumer Health Inc. revealed that ailments associated with motion sickness are severe enough for some people that they avoid certain activities that cause the symptoms. Understanding motion sickness as a disease and learning how to prevent and treat it can make flying a bit more pleasant.

WebMD, a highly regarded medical Web site, says motion sickness occurs “when the inner ear, the eyes, and other areas of the body that detect motion send unexpected or conflicting messages to the brain.” This occurs when the body is subject to rapid movement in various directions, as when a person is flying in an airplane or standing on a boat. For example, reading a book while riding in a car produces a conflict between your eyes and brain. Your eyes see the still words on a page, but your body senses movement. This disagreement causes motion sickness.

Common symptoms of motion sickness are dizziness, nausea, and fatigue. Severe cases may include vomiting and increased perspiration. To prevent this or lessen the effects, experts recommend a few simple remedies. Avoid strong odors. Don’t read while moving. If you’re flying, choose a seat over the wing for decreased movement. Also, if possible, when you’re making travel arrangements, select the largest airplane possible. Motion sickness is more common on smaller aircraft because of increased or heavy turbulence.

If you’re experiencing motion sickness, one quick remedy is to close your eyes and allow your body time to reset itself. Also, remain calm. It has been said anxiety and fear increase the effects. While prescription-strength medicines are available, over-the-counter (OTC) ones are probably your best bet. Most are available in tablet form and can be taken as soon as symptoms begin. A few products can simply be sprayed under your tongue. Motion-sickness patches and wristbands are also available. Homemade, herbal, and nontraditional remedies have also been known to combat motion sickness, though their effectiveness has not been medically proven.

If you’re experiencing severe, persistent, or recurring problems, check with your doctor for prescription medicine. If you know you’re prone to motion sickness, take any medicine at least an hour before your departure. Motion sickness can be unbearable, but knowing the symptoms, how to prevent them, and your treatment options can help make travel much easier.

—Terah Shelton