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Because individual rates of melatonin metabolism vary substantially, with older and
smaller people disproportionately affected, adjustment of the dosage is essential to
avoid decreased effects in the latter part of the night due to excessive use of "slow
release" melatonin on the one hand or disturbance of circadian patterns by use of
excessive amounts of "fast release" melatonin on the other.
Over-the-counter melatonin supplements typically contain 3-5 mg, but studies show
that even a relatively low dose of 0.3 mg per day may induce circadian levels of the
hormone well in excess of the normal level in people over 50 years old. Thus, before
deciding on a therapeutic dose to deal with insomnia, people should consult with a
physician to determine the precise amount of supplementation needed. Absent testing,
leading researchers (Mischoulon and Rosenbaum) recommend that people “work up” to
a therapeutic level, beginning with 0.1 to 0.2 mg per day.JET LAG
The sources differ in their prescription for jet lag, with Mischoulon and Rosenbaum’s
prescription the best reasoned: If melatonin is administered to contract the effect of eastward-
travel jet lag, a dose of 0.1 to 0.3 mg at the local bedtime following the flight is recommended.
Such treatment will restore the deficit in melatonin that the traveler will experience due to the
advance of bedtime at the destination. Following a westward flight, when the day is extended
rather than shortened, it would be advisable not to take melatonin at the local bedtime, when
the endogenous level of the hormone is already increased. However, it might be helpful to take
a half dose (e.g., 0.1 mg) immediately following a night or early morning awakening, as is
typically experienced in westward flights. In principle, this would facilitate resumption of sleep
and its maintenance, plus delaying the circadian phase and adjusting to the new location.
CONCLUSION
Jet lag and sleep problems associated with shift work are the most promising uses, but
many other suggested uses remain to be studied.