Melatonin use in children
I have for many years thought that the use of melatonin in children was not a good idea. I assumed that their pineal gland produced more than sufficient melatonin, but recently I have come across parents using melatonin because it is freely available in health shops and therefore assumed to be safe; secondly I have come across a number of articles on the subject. What follows is the information I have gathered so far on the use of melatonin in children.
Firstly, it is safe, and that is a good start.
Melatonin is a hormone involved in the regulation of the sleep-wake cycle. It is produced in the pineal gland through the conversion of tryptophan, to serotonin and then N-acetylseratonin, and finally melatonin. Levels begin to rise at nightfall and peak between 2am and 4 am in adults. The administration of melatonin does not appear to affect the endogenous production which is interesting, and suggests that there is no suppression of endogenous secretion by melatonin taken orally.
Melatonin can be used by children with sleep disorders. Studies have been done in children as young as six months given melatonin for sleep disorders who have failed to respond to traditional therapies. In one study nine of the patients had mental retardation and two had ADHD. The dose given was 2,5 to 5 mg or placebo at bedtime for a period of 7 to 10 days; this was then switched to an alternative arm after a four to five day wash out period. Children responding to the therapy remained on melatonin after completion of the study, and were followed at 3 and 6 months. Thirteen of the 15 children had a favourable response to melatonin, with improvement in sleep duration. Of special interest were not only the improvement in sleep but a better daytime mood and behaviour. Children with delayed sleep onset had the greatest improvement. No adverse effects were noted even in the children who continued taking the melatonin for up to a year.
Jan JE et al The treatment of sleep disorders with melatonin. Dev Med Child Neurol 1994;36:97-107
A further study by the same group showed similar results in patients ranging from three to 23 years of age and doses of melatonin between 0.5 to 4 mg. This group included 8 blind children and young adults. All patients showed some improvement and benefits were maintained up to six years in some patients. No adverse effects were noted.
Palm L et al Long-term melatonin treatment in blind children and young adults with circadian sleep-wake disturbances. Dev Med Child Neurol 1997;39:319-25
In another randomised, placebo-controlled study in 40 children (6 to 12 years of age) with chronic insomnia the children either received 5mg melatonin or placebo at 6pm over 4 weeks. Patients could continue therapy afterwards. Sleep onset and duration were significantly improved in the melatonin group, but showed no difference in the placebo group. After 18 months, 13 of 38 children evaluated had discontinued therapy without the return of the insomnia.
Smith MG et al Melatonin for chronic sleep onset insomnia in children: a randomized placebo-controlled trial. J Child Neurol 2001;16:86-92
Dodge NN et al Melatonin for treatment of sleep disorders in children with developmental disabilities. J child Neurol. 2001;16:581-4
Other studies support the benefits of melatonin in sleep disorders of children. Doses between 2,5 to 5 mg are generally used given 30 to 60 minutes before bed. Based on response, this dose can be increased after a few nights. Children with neurological injury may require higher doses. In children with night time wakening, a controlled release dosage form may be more effective.
Jan JE et al Clinical trials of controlled-release melatonin in children with sleep-wake cycle disorders. J Pineal Res 2000;29:34-9