Jet Lag 

Disturbance of body and environmental rhythms resulting from a rapid change in time zones gives rise to jet lag, which is characterized by insomnia, decreased quality of sleep, loss of concentration, and irritability. It is usually more severe after eastward travel. A variety of interventions have been tried, but none is proven to be effective. Shifting daily activities to cor- respond to the time zone of the destination country before arrival, along with taking short naps, remaining well hydrated, avoiding alcohol and pursuing activities in sunlight on arrival, might help. The dietary supplement melatonin (5 mg started the night before travel and continued for 1-5 days after arrival) has been reported to facilitate the shift of the sleep- wake cycle and decrease symptoms in some patients.