What are the long-term side effects of taking melatonin as an oral supplement?
The couple of articles I have read are inconclusive:
Although you can't overdose on melatonin, doctors aren't sure whether relying on it can affect you negatively.
The long-term side effects of melatonin have not been well studied. If you have epilepsy or are taking blood thinners such as coumadin (Warfarin), talk to your doctor before using melatonin.