A jet lag can occur after a long flight that crosses various time zones. The biological clock no longer corresponds to the local time. In general, a jet lag causes more problems when the day is shortened, when flying from West to East. Sensitivity to jet lag varies from person to person and often increases with age.
The following symptoms can occur:
- Sleep disorders: struggling to fall asleep, waking too early or disrupted sleep
- Drowsiness during the day
- Reduced mental and physical performance
- Reduced appetite
- Gastro-intestinal problems
The symptoms usually disappear after a few days.
Adopt the local rhythm of meals and bedtime immediately after arrival.
Take time off
Do not schedule any important meetings within 24 hours of arrival.
Avoid rich meals and too much alcohol or coffee.
Have a short daytime siesta (maximum of 20 to 30 minutes) if necessary, but do not sleep too long as this can undermine sleep at night.
The most important factor that regulates the biological clock is light.
Following a westward flight:
- Remain awake whilst it is still light, go outside in the afternoon.
- Try to sleep in a darkened room as soon as the sun sets.
- Avoid bright daylight in the morning.
Following an eastward flight:
- Go outside in the morning.
- Avoid bright light in the evening, for example by wearing dark sunglasses.
Some people experience improved sleep after taking melatonin:
- Following a westward flight, take 0.5 mg if you wake up too early (before 5 am).
- Following an eastward flight, take 5 mg at night before going to bed.
If melatonin does not help, then you can take a short-acting sleeping tablet for the first night(s).