Jet Lag

Your ‘body clock’ is set to a cycle of day and night, and helps control the release of hormones at appropriate times. When it gets dark, the brain produces a hormone called melatonin. This makes you feel tired and helps prepare your body for sleep. During daylight hours, the production of this hormone stops.

When you travel to a different time zone, your body clock will be out of sync with the natural cycle of day and night. This is jet lag. It means that your body will need to produce melatonin at different times than usual.

Most people find it easier to adjust to a new time zone when flying west. When you travel west, it gets dark later in the day, and you need to stay up a bit later. When travelling east, it gets dark earlier. This means that to adjust to the new routine, you would need to go to sleep earlier than usual.

The symptoms of jet lag vary between travellers. They also vary depending on the distance you are travelling. The further you travel, and the more time zones you cross, the more noticeable your jet lag will be.

The primary symptom of jet lag is a disturbed sleep cycle. As a result, you may feel tired and find it difficult to concentrate. A disturbed sleep cycle has an impact on your body and can cause additional symptoms like:

• nausea, indigestion, diarrhoea, and constipation
• changes in appetite
• confusion and lightheadedness
• feeling irritable
• feelings of disorientation and clumsiness
• problems with memory
• excessive sweating
• headaches
• sore muscles
• irregular periods (may affect women who travel on a regular basis)

Depending on how far you have travelled and how well you are adjusting, your jet lag symptoms may persist for several days. In most cases they will subside within two days.

You may not be able to completely avoid jet lag, but there are a few ways to minimise the symptoms and help you adjust to the local time. Melatonin tablets can reduce the time it takes you to settle into the new routine. They contain the hormone melatonin, which your body produces naturally to regulate your sleep cycle.

Taking one tablet every night for the first few days will help you sleep at the right time and feel well during the day. The tablets compensate for the fact that your body is not producing melatonin at the right time. You will find it easier to fall asleep, and get up in the morning. After a few days your body should get used to the new schedule.

In addition to taking melatonin tablets you can try to settle into the new routine while you are still on the plane. Try to sleep when it is night time at your travel destination, as this will help you stay up when you arrive. Likewise, if you are going to arrive in the evening, delay going to sleep until you arrive. The faster you manage to adjust to the time at your destination, the milder your symptoms of jet lag will be.

It helps if you begin your journey well rested. If you begin your journey tired, you're more likely to encounter symptoms. It's also important that you drink plenty of water as dehydration makes some jet lag symptoms worse, including confusion and lack of concentration.

Although drinking plenty of fluids will help you feel better, drinking alcohol will not. Alcohol has a negative impact on the quality of your sleep and should be avoided, or enjoyed in small quantities.

You may find it helpful to drink caffeine when you need to stay up longer or when getting up early. But you should make sure that you do not consume any caffeine too close to when you're planning to sleep.

Each film-coated tablet contains 3mg of melatonin. The standard dose is 3mg (1 tablet) daily for a maximum of 5 days. The first dose should be taken upon arrival at your destination at the habitual bed-time.

Due to the potential for incorrectly timed intake of melatonin to have no effect, or an adverse effect, on re-synchronisation following jet-lag, Melatonin 3mg film-coated tablets should not be taken before 8pm or after 4am at destination.

Food can enhance the increase in plasma melatonin concentration. Intake of melatonin with carbohydrate-rich meals may impair blood glucose control for several hours. It is recommended that food is not consumed 2 hours before and 2 hours after intake of Melatonin 3mg film-coated tablets.

As alcohol can impair sleep and potentially worsen certain symptoms of jet lag (e.g. headache, morning fatigue, and concentration) it is recommended that alcohol is not consumed when taking Melatonin 3mg film-coated tablets.

Melatonin 3mg film-coated tablets may be taken for a maximum of 16 treatment periods per year.

Melatonin must not be used with any other sedative medications or sleeping tablets.

Melatonin can interact with other medications - please check with your doctor if you are taking any other medicines (prescription or over the counter).

Possible side effects of the medication

WARNING: Melatonin will cause drowsiness therefore should only be used at bedtime and not when drowsiness could pose a danger to your safety and well-being (e.g. if driving or using machinery).

Drowsiness/sleepiness, headache, and dizziness/disorientation are the most frequently reported adverse effects when melatonin is taken on a short-term basis to treat jet lag. Drowsiness, headache, dizziness, and nausea are also the adverse effects reported most frequently when typical clinical doses of melatonin have been taken for periods of several days to several weeks by healthy persons and patients. For a full list of side effects, please refer to the patient information leaflet.