Some people use the medication melatonin. In theory, it helps to reset your body clock by indicating that it will soon be night-time. When the Cochrane Review examined all the best evidence in 2002 it concluded that melatonin can be useful in combatting jet lag, but that the pharmacology and toxicology of melatonin needs more systematic study.

Whether or not health authorities recommend it depends on where you live. The Centers for Disease Control in the US includes advice on using melatonin for jet lag in their Yellow Book of official recommendations for travellers. In the UK, the NHS does not recommend it due to there not being enough evidence for its effectiveness.

Melatonin does bring risks. In the short-term, this medication can cause dizziness and nausea, while longer term daily use has been linked to a higher risk of heart failure, as well as an increased risk of hospitalisation from heart failure and increased risk of death overall. Anyone considering taking a new medication should consult their doctor first.

Getty Images In one study, cabin crew with demanding schedules were found to have much higher levels of cortisol in their systems – a sign of stress (Credit: Getty Images)Getty Images
In one study, cabin crew with demanding schedules were found to have much higher levels of cortisol in their systems – a sign of stress (Credit: Getty Images)

For short-term use of melatonin for jet lag, if you time the doses incorrectly, it can backfire. You can confuse your body clock entirely and make your jet lag worse. Online jet lag calculators can be useful here, but even then, some people dislike the feelings of drowsiness melatonin can cause, or can't take it due to health conditions such as epilepsy or due to interactions with other medication.