insomnia
"Melatonin helped me to fall asleep (I have severe insomnia), and usually keeps me asleep for some hours, sometimes the entire night, which to me is incredible. It helped me get off the poisonous benzodiazepines. I did need at least 3mg to feel the effect, so if you're not feeling it, increasing doses might help. As a side effect, I think it lowered my blood pressure during the night, although I'm not sure. Studies did confirm it has this potential."