US-based online store iHerb has suspended sales of melatonin gummies to Australia. This comes after a rise in reports of non-fatal overdoses in Western Australia in children who took these popular supplements. This latest move raises fresh concerns about the safety of these non-prescription sleep aids. I have been a sleep researcher and a psychologist treating children with behavioural sleep problems for more than 20 years. Here’s what’s great and not so great about using melatonin to help children sleep.