You don't like melatonin?
Personally the reason why you get drowsy (if this is the reason you are referring to) is because the wrong dosage is being sold in stores. The typical dosage is 3mg and even at half that it is still too high.
I have a study (if you want it I can provide it) that shows melatonin at different dosages and plasma levels the next morning. The half life is 8-10 hours and plasma levels upon waking were tested. At the 3mg dosage plasma levels were like 24000 pg/mL or something like that (not sure if those units are exact as I am too lazy to look at study) and at the 0.3mg dosage, plasma levels were, obviously enough, 295 pg/mL. The effects felt were the same at both dosages. In other words USE LESS

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