Melatonin to Fight Insomnia: Timing Is Key
Researchers Say Treatment Must Be Linked to Individual Sleep Patterns
Oct. 25, 2005 -- The dietary supplement melatonin may be an effective
treatment for sleep problems caused by disturbances in the body's internal
clock, but treatment timing may be everything.
In a study published in the October issue of the journal Sleep,
Northwestern University researchers reported that melatonin was most effective
in resetting the body's internal, or circadian, clock when it was timed to the
individual's sleep patterns.
The study included patients who habitually went to sleep very late at night
and had difficulty waking up when they needed to in the morning. They reported
difficulty falling asleep at conventional bedtimes.
When this occurs because of disturbances in circadian rhythms it is known as
delayed sleep phase syndrome (DSPS).
"This is a fairly common problem that can have a tremendous impact on
school and work performance and all aspects of a person's life," researcher
Margarita Dubocovich, PhD, tells WebMD. The study notes that about 10% of
people with insomnia may have DSPS.
Setting the Stage for Sleep
Circadian rhythm disorders are disruptions in the body clock that regulates
when a person wakes and sleeps over the course of a 24-hour day. Jet lag, shift
work, medications, and changes in routine can all disrupt the body's internal
clock, but no obvious external influences exist in people with DSPS.
Melatonin is a hormone produced naturally by the brain to regulate sleep. In
most people levels increase in the evening, setting the stage for sleep.
While some studies have shown melatonin supplements to be effective for
treating circadian rhythm disorders like DSPS, the timing of treatment has not
been well understood.
, according to a report from the Agency for Healthcare
Research and Quality.
In the newly published study of 13 people, Dubocovich found that melatonin
worked best when treatment times were determined by the patient's individual
sleep schedule. There was no significant effect on sleep onset or offset (how
early they awakened from sleep).
"Melatonin works in two ways," Dubocovich says. "If you only
want to induce sleep you can take it about two hours before you want to go to
She warned, however, that people with sleep problems should not
self-medicate with melatonin.
"This is all very complicated," she says. "If you give melatonin
at the right time of day it can be effective. But if you give it at the wrong
time it can make sleep problems worse."
Sleep medicine specialist Steven W. Lockley, PhD, agrees. In an editorial
accompanying the paper, Lockley wrote that identifying the individual patient's
biological sleep patterns is an important challenge for the diagnosis and
treatment of circadian rhythm sleep disorders.
Lockley is with the Harvard Medical School Division of Sleep Medicine.
"It is clear that both the duration and the timing of sleep are
important," Lockley tells WebMD. "If you can't get to sleep at the
right time you don't tend to sleep very well. That is true for people with
delayed sleep phase syndrome and for everyone."