Originally Posted by Blackcat31:
It may be considered safe in most aspects but I wouldn't go that far as to say it's the least dangerous.
My DS suffered from insomnia and other sleep issues and my pediatrician would NOT recommend melatonin stating NO long term studies have been done and unless ALL other things fail. We found a solution with regular routine, soothing sounds and diet adjustments. 
From Livestrong.com
According to the National Institutes of Health, melatonin appears to be an effective treatment for sleep disturbances in children with developmental and neurobehavioral disorders, such as autism, anxiety disorder, mental retardation, Asperger's syndrome and attention-deficit hyperactivity disorder. Melatonin can help these children fall asleep faster and stay asleep longer. Some parents also use melatonin as a treatment for insomnia in children with normal development, but no studies have evaluated this use.
Safety Considerations
The University of Maryland Medical Center states that melatonin can be a safe supplement for children when it used in low doses, under the guidance of a qualified practitioner. However, the NIH considers the product to be inappropriate for use in most toddlers. The benefits associated with melatonin are only worth the risks when a toddler's sleep disturbances are significantly disruptive to his health or development, and when drug-free treatment options have failed.
Possible Risks:
Melatonin can trigger several possible side effects in toddlers. The UMMC states that high doses, exceeding 1 to 5 milligrams, can cause seizures in children under 15 years of age. According to the NIH, melatonin can alter the production of reproductive hormones, particularly in adolescents. No large-scale, well-designed studies have investigated the effects of melatonin supplements on a toddler's developing endocrine system. The NIH reports a link between melatonin supplements and uncomfortable side effects such as headache, stomach cramps and mood disturbances.
Read more: http://www.livestrong.com/article/27...#ixzz2htjQXrTy
Ita there are usually better more appropriate things to try for most people, children included.
But I'd be willing to bet the study the NIH was referencing was the one where the dosage was 50mg+. In that one, yes, people experienced upset tummies and headaches......but the same could be said for too many brussel sprouts you know?
Eat to much of anything it's going to cause you trouble, heck, drink too much WATER it can cause the same and even KILL you.
But with the recommended dose being .5-3mg people rarely (never?) experience such side effects. It's far lower than our own bodies produce so it wouldn't make sense.
Only in these studies where they've literally had people consume entire bottles of the pills, has there been an issue. Imho, thats not a study, just bunk researchers trying to peg a very safe supplement dangerous so pharmaceutical companies can get their grubbies in on "regulating" it more intensely (ie....be able to charge the general public more for it).