A characteristic set of symptoms experienced by many people when subjected to the constant changes of position caused, for example, by the pitching and rolling motion of a vessel at sea. Depression, giddiness, nausea and vomiting are the most prominent.
Although the vast majority of people appear to be liable to this ailment at sea, not all suffer alike. Many endure acute distress, whilst others are simply conscious of transient feelings of nausea and discomfort. A smaller proportion of people suffer from air and car sickness. The symptoms are a result of overstimulation of the organs of balance in the inner EAR brought about by continuous changes in the body's position. Movements of the horizon worsen this situation.
The symptoms generally show themselves soon after the journey has started, by the onset of giddiness and discomfort in the head, together with a sense of nausea and sinking at the stomach, which soon develops into intense sickness and vomiting. Most people recover quickly when the motion stops.
Innumerable preventives and remedies have been proposed. Cinnarizine may be dimenhydrinate and promethazine are commonly taken for motion sickness.