Jet Lag

Jet lag typically lasts between two and five days, though this varies depending on the number of time zones crossed and the direction of travel. As a general rule, the body adjusts at a rate of roughly one to one and a half time zones per day. Travelling east tends to cause more severe and longer-lasting jet lag than travelling west, because it requires you to fall asleep earlier than your body clock expects,  something most people find harder than staying up later. Crossing more than five or six time zones usually produces the most noticeable symptoms. Treatment with melatonin and careful management of light exposure and sleep timing can help shorten recovery time considerably.

The timing of jet lag treatment depends on your destination and travel schedule. Melatonin is most effective when taken at bedtime in your destination's time zone. This can begin on the evening of your arrival and continue for up to five days. Some travellers also benefit from adjusting their sleep schedule by one to two hours in the days leading up to their trip, shifting gradually towards the new time zone. If travelling east, this means going to bed and waking up earlier; if travelling west, the opposite. Light exposure management,  seeking bright light in the morning or avoiding it in the evening,  can also be started before departure. Planning your treatment through Peak Pharmacy's online service ensures you have your medication ready before you fly.

Jet lag tends to be more severe when travelling east because it requires you to advance your body clock,  essentially forcing your body to fall asleep and wake up earlier than it naturally wants to. Most people find it easier to stay up later than to go to sleep earlier, which is why travelling west (delaying the body clock) is generally easier to adapt to. For example, flying from the UK to Thailand (six hours ahead) means your body expects to be awake when the local time says you should be sleeping. The greater the number of time zones crossed in an eastward direction, the more significant the disruption and the longer recovery tends to take.

No. Unlike in many other countries where melatonin is sold as a dietary supplement, in the UK, melatonin is classified as a prescription-only medicine (POM). This means it must be prescribed by a qualified healthcare professional following an assessment. You can obtain a prescription for melatonin through Peak Pharmacy's online doctor service by completing a short consultation. Buying melatonin supplements from abroad,  including melatonin gummies or capsules marketed as dietary supplements,  is not recommended, as these products are not authorised for UK sale and are therefore unregulated.

Melatonin is generally well tolerated, and serious side effects are uncommon. The most commonly reported effects include drowsiness (which is expected, as the medication is designed to aid sleep), headache, dizziness, nausea and dry mouth. Some people may experience vivid dreams or restless sleep during the first night or two. Because melatonin can cause drowsiness, you should not drive or operate machinery after taking it. Melatonin is not recommended for people with autoimmune conditions, severe liver or kidney impairment, or those with a known allergy to any of the ingredients. If you are pregnant, breastfeeding or taking other medications, consult a prescriber before use.

You can reduce the severity of jet lag with several non-medication strategies, though they may not eliminate symptoms, especially after long-haul flights. Useful approaches include gradually adjusting your sleep schedule by one to two hours in the days before travel, staying well hydrated during the flight and avoiding excessive alcohol and caffeine, setting your watch to the destination time zone as soon as you board, seeking bright daylight at strategic times after arrival to help reset your body clock, and trying to eat meals at local times as soon as possible. These strategies work well alongside melatonin treatment and are particularly helpful for frequent travellers looking to minimise disruption.