Jet lag and motion sickness

Jet lag. Present day aircraft operating round northern and southern latitudes cross time zones at almost the same rate as the earth rotates, and it is these rapid transmeridian transitions that lead to the syndrome commonly referred to as jet lag. On arrival at their destination, individuals find themselves out of synchrony with the social and time cues of their new environment and, until they adapt, may experience symptoms such as malaise, gastrointestinal disturbance, loss of appetite, tiredness during the day and poor sleep. The severity and exact nature of the problems vary with the direction of travel and the number of time zones crossed, and some people react more unfavourably to intercontinental travel than others. Clearly, with increasing numbers of passengers undertaking such journeys, there is considerable interest in strategies to reduce the immediate effects of jet lag or to facilitate acclimatisation. Motion sickness is a generic term which embraces seasickness, airsickness, carsickness, space sickness etc, names that identify the provocative environment or vehicle. It is a normal reaction of humans to exposure to certain motion stimuli that occur during passive transportation.