Brand name: MELOSET
(MEL, MLT, Melatonin)
Use of complementary... Diagnosis and... Innovative Integrated...
Description
Melatonin is a hormone produced naturally in the pineal gland at the
base of the brain. It is important in regulating sleep, and may play
a role in maintaining circadian rhythm, the body's natural time clock.
The hypothalamus keeps track of the amount of sunlight that is taken
in by the eye. The less sunlight, the more melatonin that is released
by the pineal gland, thereby enhancing and regulating sleep. Melatonin
can also be taken an over-the-counter supplement mainly sold in health
food stores and pharmacies.
General use
A variety of medical uses for melatonin have been reported but its
current popularity stems from its use as a sleep aid and to reduce
jet lag . However, medical experts caution that melatonin is not a
harmless substance without risks. Natural melatonin production decreases
with age and the decrease is associated with some sleep disorders ,
particularly in the elderly.
According to a Gallup Poll survey taken in 1995 for the National Sleep
Foundation, about half of all American adults experience either occasional
or chronic sleep problems. The use of melatonin supplements became
popular in the mid-1990s as a way of treating insomnia. Numerous scientific
studies have supported this claim, although there are a few studies
that cast doubt on its effectiveness. People reporting the most benefit
generally are those with mild and occasional insomnia and trouble falling
asleep. It is not generally recommended for use on a regular basis
since its long-term consequences are not known.
The second most popular use of melatonin is to ease the effects of
jet lag, a physical condition caused by the disturbance of circadian
rhythms, usually associate with air travel across several time zones.
Whether or not melatonin works to relive jet lag is still up in the
air, since various small-scale studies have yielded conflicting results.
In one study of airline passengers, melatonin relieved jet lag when
taken before, during, or after an eastward flight but was less effective
on westbound flights. Another study indicated it was effective only
if taken before a flight. A 1999 study by researchers at Columbia University
of 257 travelers found melatonin was no more effective than a placebo
as a jet lag antidote.
Melatonin has also been touted by some as an anti-aging agent following
the results of an experiment in Italy. An Italian researcher reported
that in a laboratory experiment, older mice appeared to grow younger
and live longer after being on melatonin. However, there have been
no studies in humans to support this claim. Animal tests in Spain and
China have appeared to show that melatonin can help prevent some cancers,
heart disease , and brain degeneration. Further studies on the benefits,
long-term effects, and proper dosage are being conducted through the
National Institutes on Aging.
In laboratory and animal experiments, melatonin appears to protect
cells and boost the immune system. Melatonin supplementation is sometimes
part of a holistic treatment regimen for people with HIV or AIDS. There
have been no human trials that support this claim.
Preparations
Melatonin is available over the counter in varying doses of up to
3 mg per tablet. However, a fraction of this is required for insomnia,
usually about 0.3 mg or less. Too much melatonin or taking it at the
wrong time can interrupt normal circadian patterns. Melatonin is produced
at its highest level in the pineal gland during darkness. Since melatonin
occurs naturally in some foods, it can be sold as an over the counter
dietary supplement. It is only one of two hormones (the other is DHEA)
not regulated by the U.S. Food and Drug Administration (FDA). Natural,
animal, and bovine melatonin supplements contain actual extracts from
pineal glands. Synthetic melatonin is made from non-animal ingredients
and is suitable for vegetarians. It is similar in molecular structure
to melatonin produced in the body.
The proper dosage is not known, but it appears to differ greatly depending
on the individual and extent of the sleep disorder. Persons starting
the hormone should begin with a very low dose, 100-300 mcg, which is
0.1-0.3 mg, or less, and gradually increase the dosage if needed. Melatonin
is quick-acting and should be taken about 30 minutes prior to bedtime.
For jet lag, the general recommendation is 300 mcg just before boarding
the flight and 1.5 mg after arrival before going to bed. Melatonin
should not be taken during the day.
Precautions
Women who are on estrogen or estrogen replacement therapy should not
take melatonin without consulting their doctor. Since the safety of
melatonin use during pregnancy has not been adequately studied, women
who are pregnant or breast feeding a child should not take melatonin.
Also, women who are trying to get pregnant should avoid using it since
some research suggests it may have a contraceptive effect. Studies
in animals suggest melatonin can constrict blood vessels, which can
raise blood pressure. Therefore, persons with hypertension or cardiovascular
problems should consult with their doctor before taking the hormone.
It is not recommended for people with lymphoma or leukemia, and should
not be used by children.
Side effects
