The study is based on more than 25,500 children and teenagers in Sweden who received melatonin on prescription.
"We noticed that certain types of injuries, including self-harm and poisoning, increased before prescribing melatonin and decreased sharply after melatonin treatment began," says Sarah Bergen, associate professor at the Department of Medical Epidemiology and Biostatistics at Karolinska Institutet, who led the study.
Self-harm decreased dramatically in young girls
The researchers looked at the risk of self-harm in the same person during periods with or without melatonin treatment by comparing the risk just before starting treatment with the subsequent twelve months. Over 87 percent of those followed in the study had at least one psychiatric diagnosis: the most common was ADHD, anxiety, depression or autism.
Self-harm was about five times more common in girls than in boys. It was also among the young girls that self-harm decreased dramatically.
Wants to see increased subsidization
There is currently no research on whether similar results could be seen when using melatonin also in other groups, such as adults with the same diagnoses. Sarah Bergen says she would love to look into it, but that it's harder to access data and statistics for adults because melatonin in those cases is primarily prescribed by primary care.
She also hopes that the results of the study can lead to the young people who can be helped by melatonin actually having access to it.
– For children, melatonin is only subsidized if they also have ADHD. This study clearly shows that melatonin improves the situation even for children and adolescents with anxiety and depression, so I hope that decision-makers can open their eyes to it and that it can be changed.