The three months is because there have been studies showing it is safe for that long. But afaik there have been no studies suggesting that it would not be safe

The three months is because there have been studies showing it is safe for that long. But afaik there have been no studies suggesting that it would not be safe to take it for longer. Gwern has a page (with a very pro-Melatonin message) with lots of links: http://www.gwern.net/Melatonin http://www.gwern.net/Melatonin