07/07/2013 02:08 EDT | Updated 09/06/2013 05:12 EDT

Melatonin no 'magic pill' for getting healthy kids to sleep

Melatonin is marketed as a natural sleep aid but it's potentially risky for healthy children to use long term, Canadian pediatricians say.

Difficulties settling, falling asleep and staying asleep affect up to 25 per cent of children generally and up to half of those with physical and mental health problems, according to the Canadian Sleep Society.

Melatonin is a hormone of darkness that is part of the sleep cycle. People can buy melatonin supplements at pharmacies and health food stores to overcome jet lag or occasional insomnia.

But long-term use by healthy, developing children isn't advised, said Dr. Shelly Weiss, a neurologist at the Hospital for Sick Children in Toronto, who is studying the use of melatonin supplements for improving sleep in children with epilepsy.

"It's being touted as this magic pill," said Weiss. "There's definitely concern that people are going to use it more widely and not appreciate that their child can learn to sleep better without a hormone being given."

Melatonin supplements contain between 25 to 50 times as much melatonin as the body makes at night, Weiss noted.

"There's definitely potential risk, mostly to delayed puberty or delayed development in children who have taken it for a long time," said Weiss, who is also president of the Canadian Sleep Society and an associate professor at the University of Toronto.

For children with neurologic problems such as autism and cerebral palsy, melatonin definitely helps them to sleep when combined with behavioural strategies, Weiss said.

Toronto pediatrician Dr. Marvin Gans suggests melatonin to families of children with autism or ADHD. "For those parents, it's been a godsend."

For short-term circumstances like jet lag, it is fine, Gans said. But he also cautioned against long-term use in children without neurological problems since its long-term effects haven't been studied.

- READ: 7 healthy sleep tips for children

"Certainly there's a buzz on it now," said Gans. "That's part of our quick-fix society where people want to get the kids to sleep quickly. We play until X hour and then they want them to be asleep in the next three minutes."

Zeb Fulcher, 8, of Windsor, Ont., has been taking melatonin with his ADHD medication for about two years.

"Before he would be up several times a night," recalled mother Marie Fulcher. "We would go to bed. He'd be up in the living room saying he can't fall asleep. And since, he doesn't do that anymore. He lays in bed, reads for a little while and then he's right off to sleep without issue."

Zeb also sees a difference with the melatonin. "You chill out from it and chill out so much that you fall asleep."

For children without neurological problems, doctors recommend teaching parents how to perform routines to get children to fall asleep.