"i&#039;m 49, menopausal and i am detoxing methadone (for cancer pain) and every night i find myself wide awake, body and mind despite rx sleeping pills. i was taking  2- 3mg tabs of melatonin with fairly good results. i have since learned that that is considered a high dose. however i picked up a new bottle and inadvertently got 5mg tabs so for 4 nights i was taking 10mg and it had an opposite effect. i was anxious, my heart was racing, i became quite depressed through the day, and of course i was wide awake. so if you are having any of those problems with melatonin then maybe try a lower dose. i have since learned that a body normally makes .3mg/day so much lower doses make sense. sweet dreams..."