Definition of Jet lag

Jet lag: A temporary disorder that causes fatigue, insomnia, and other symptoms as a result of rapid air travel across time zones.

Other symptoms of jet lag include anxiety, constipation, diarrhea, confusion, dehydration, headache, irritability, nausea, sweating, coordination problems, and even memory loss. Some individuals may report additional symptoms, such as heartbeat irregularities and an increased susceptibility to illness.