Up to 89% of children with autism have trouble sleeping. Melatonin is a naturally-occuring hormone that is important in regulating people's body clocks and researchers at the University of California in Sacramento carried out a four-week study on 18 children, between two and 15, with either autism or fragile X syndrome, to see whether melatonin could help them with their sleep problems. The children were given either 3mg of melatonin or a placebo every night for 2 weeks and then swapped over into the other group. The study found that treatment with melatonin was associated with longer sleep each night (by 20 minutes), less sleepiness and getting to sleep earlier (42 minutes on average).
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