Jet lag: what to know after travel

Jet lag follows rapid travel across time zones, when the brain's sleep-wake rhythm is still aligned with the departure location. You may find it difficult to sleep at the local bedtime, wake too early, or feel daytime sleepiness when you need to be alert. Headache, poor concentration, irritability, and appetite changes can accompany the adjustment.

Symptoms tend to be more noticeable after crossing several time zones and can be affected by travel fatigue, dehydration, alcohol, illness, or irregular sleep before the journey. Jet lag is different from insomnia when symptoms continue without a travel-related time-zone change.

Use the destination's clock soon after arrival: eat, sleep, and get up at local times. Seek natural daylight during the part of the day that supports your new schedule, and keep evening light low when preparing for sleep. Take a short nap only if needed, because a long daytime sleep can make the next night harder.

Drink water, choose light meals, and avoid alcohol close to bedtime. Do not drive or make safety-critical decisions while very sleepy. A travel health consultation can help if you cross time zones often, have a sleep condition, or are considering medicines or melatonin.

Arrange medical advice if sleep disruption or daytime sleepiness persists after your body has had time to adjust, repeatedly interferes with work or driving, or occurs without recent travel. Seek urgent help for confusion, fainting, severe headache, chest pain, or breathing difficulty rather than assuming these are jet lag.

Ask how to shift your sleep schedule before a trip, whether a medicine is suitable for you, how to manage jet lag with your existing conditions, and when ongoing symptoms should be assessed for insomnia or another cause.