Melatonin is a fascinating human hormone, produced in the pineal gland of the brain. It
affects the body’s circadian rhythm and sleep patterns, and endocrine (hormone)
secretions. Synthesized from the amino acid tryptophan, it becomes serotonin as an
intermediate product. Its production is inversely related to the amount of light a person
gets, varies with age, and may be increased by meditation or music therapy. It is rapidly
inactivated, so that with lower doses (3 mg or less by mouth) one can drive or use
machinery 4-5 hours afterward. Use has been reported or studied in 30 conditions,
ranging from sleep disorders and disruptions, depression, seizures and other brain
conditions, to cancer and sunburn.
Sleep conditions have been studied the most, with varying conclusions. As is often true,
methodology, patient selection and product formulation vary, making overall conclusions
difficult. Although the measurable marker of sleep efficiency does not seem to improve
with melatonin, subjective reports of sleep quality, alertness, daytime sleepiness and
fatigue improve with use for jet lag, and the time it take to fall asleep (sleep latency) in
general insomnia. Sustained release preparations may be better for sleep maintenance, but
have not been sufficiently studied. Unfortunately, melatonin does not seem to yield
improvement in measurable markers for those working rotating or graveyard shifts; I
found no notation of subjective benefits for this use. Special needs children may have
benefits, but parents need to check with the provider for these specialized uses.
A prescription, sustained release preparation is being studied in France for the indication
of sleep. The only other common self medication situation in which melatonin is likely
effective is nicotine withdrawal.