injuries and poisoning
Motion Sickness
Introduction
Motion sickness (also known as car, sea, train, or air sickness) involves a group of symptoms, particularly nausea, caused by movement during travel. While traveling, people feel nauseated and dizzy and may break into a cold sweat and start hyperventilating. Doctors base the diagnosis on symptoms and the situations in which they occur. Ways to help prevent motion sickness include keeping the gaze and head as still as possible, getting some fresh air, not reading, not smoking or drinking alcoholic beverages before traveling, and sometimes taking a medication by mouth or skin patch. Eating soda crackers or sippingginger alemay help relieve the nausea, but once vomiting has started, a medication such asondansetronorgranisetronmay be needed. Motion sickness occurs when the parts of the inner ear that help control balance (including the semicircular canals) are overstimulated, as can occur when motion is excessive. It can also occur when the brain receives contradictory information from its motion sensors—the eyes, the semicircular canals, and the muscle sensors (nerve endings in muscles and joints that provide information about body position). For example, motion sickness commonly occurs during boat travel, when the boat rolls and rocks while the person looks at something that does not move, such as a wall. In this case, the rolling and rocking do not match the lack of movement in the wall. The brain can also receive contradictory information if a person sees something moving excessively despite the person being still. This type of contradictory information may be received when, for example, a person watches a movie taken with a camera that shakes, or plays a video game. Motion sickness may also occur in a moving car or other vehicle or on playground or amusement park rides. Space travelers can also be affected. 