Alleviation of jet lag by melatonin: preliminary results of controlled double blind trial.

Alleviation of jet lag by melatonin: preliminary results of controlled double blind trial Jet lag is an ill defined phenomenon resulting from rapid flight across several time zones.' It is considered to be due to desynchronisation of circadian rhythms, such as the sleep-wake cycle, with local time and to lack of sleep. ' A means of rapidly resynchronising body rhythms to local time would benefit people who suffer badly from jet lag. Various remedies for alleviating jet lag have been proposed: manipulation of dietary intake and, more recently, appropriate exposure to'bright light have been used, though both are time consuming.2 3 We previously suggested that melatonin, a methoxyindole secreted by the pineal gland, might be simpler and more effective in treating jet lag.4 In view of its resynchronising properties in animals,5 its ability to transduce light-dark information, its hypnotic effects in man, and its low toxicity we examined whether it helped people adapt to new time zones. Seventeen healthy volunteers. (10 women and seven men aged 29:-68) were recruited from the university staff and their families. All gave their informed consent to the study, which was authorised by the University of Surrey ethical committee. The subjects flew from London to San Francisco (eight time zones west), where they remained for 14 days'so that they had adapted to local time before their return home. Subjects taking placebo Subjects takig melatonin Visual analogue scores (0=insignificant, 100=very bad) showing severity of jet lag among eight subjects given melatonin and nine subjects given placebo. Subjects wore wrist meters (provided by Professor A Borbely, University of Zurich) for roughly one week'before and 33 days after departure to continuously monitor activity. For two days before departure and on days 1-7, 14, 15, 21, and 22 after their return each subject collected six hourly sequential urine samples, kept a daily sleep log, and recorded their mood and oral temperature every two hours from 0800 or awaking, whichever was the later, until 2400 or bedtime, whichever was earlier. They also performed logical reasoning and letter cancellation tests every four hours from 0800 to 2400 on the days specified above. The results of the psychological test and hormone analyses will be reported later. For three days before their return flight the subjects took a daily dose of melatonin (5 mg in gelatin lactose) or placebo at 1800 (local time). On their return to.Britain they continued taking the same preparation …