Eleven youngsters with autism ages 4 to 10 fell asleep more quickly and slept longer when given low-dose supplements of melatonin, says Beth Malow, MD, director of the Sleep Disorders Center at Vanderbilt University in Nashville, Tenn.
The supplements didn't appear to cause any side effects, suggesting parents can continue to give them to their kids as long as needed, she tells WebMD.
Studies have shown that as many as 70% of children with autism suffer from sleep problems, according to Andrew Zimmerman, MD, of the Kennedy Krieger Institute in Baltimore, who specializes in treating autism.
Other research points to a deficiency of melatonin -- the body's natural sleep hormone -- as the culprit, Malow says. Secreted at night by the pineal gland in the brain, melatonin is thought to control sleep cycles, which are frequently disturbed in the elderly -- and kids with autism, she says.
Importance of Good Sleep Habits
To determine whether supplemental melatonin can overcome the problem, Malow and colleagues are studying children with autism who toss and turn for at least 30 minutes a night, three nights a week, before falling asleep.
In the ongoing study, parents go through an educational program on good sleep habits. They're taught to make sure their offspring maintain a bedtime routine, going to bed at the same time every night, for example. And if youngsters do get up in the middle of the night, parents are told to tuck them back into their own beds, not let them slip under the covers between mom and dad.
Then, the children are given melatonin in liquid form, a half hour before bedtime, every night. Doses are increased every three weeks until the youngsters can fall asleep within 30 minutes of bedtime at least five nights a week.
"We give it as a liquid because not all children with autism can swallow pills easily," Malow says.
So far, 11 kids have completed the first, four-month phase of the study. After 16 weeks of supplementation, the average time it took for them to fall asleep dropped from 38 minutes to 22 minutes.
One milligram a night did the trick for three of the 11 youngsters, Malow says. Six required 3 milligrams, and only two children needed 6 milligrams, she says.
They also slept longer, and parents reported they had less trouble getting their kids to agree to go to sleep, Malow reports.
Additionally, the children exhibited fewer of the compulsive and ritualistic behaviors that can accompany autism, she says.
The findings were presented here at the annual meeting of the American Neurological Association.
Synchronizing Natural Sleep Patterns
While there have been reports of bed-wetting, seizures, and daytime drowsiness among children given melatonin supplements, "we didn't see any of those problems. These are relatively small doses and they seem benign," Malow says.
The children are continuing to take the supplements, and the researchers plan to see how they're sleeping after six months.
"There's some evidence that the melatonin supplements synchronize the natural sleep pattern and you can stop giving it after six months to a year," Malow says.
Proper sleep hygiene is a huge part of the equation, Malow stresses. "If kids watch videos late at night, that's going to interfere with their sleep. They'll be all hyped up, and the light will interfere with the body's own melatonin," she says.
The researchers also plan to collect blood and urine samples to confirm whether children with autism are deficient in melatonin and whether supplementation brings levels back to normal.
Zimmerman, who was not involved with the work, tells WebMD that he often prescribes supplemental melatonin to his young patients with autism.
"It's readily available and easy to use," he says. "My experience is that it helps to get them to sleep, but doesn't always help them stay asleep. I'm glad to see the children in the study had longer sleep duration."
The big question is how long to give melatonin to children, he says. "This is important work as it helps answer that question."
Once the safety and effectiveness of supplemental melatonin is confirmed in more children, the researchers plan to conduct a larger trial pitting melatonin and behavioral therapy against behavioral therapy alone, Malow says.