melatonin!
its natural and works GREAT
nothing works for me but this
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I took somonex once & it put me out.
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don’t know?
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I take valerian root in capsule form and four out of five times I go straight to sleep. It also calms the mind when it is racing over problems all night long, it makes that stop I find.
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There are basically just two options when it comes to over the counter sleeping aids. You have your antihistamines, and you have your herbal-based aids. Antihistamines work by affecting your central nervous system, making it slow down and thus causing you to feel drowsy. It is the same sort of medication used for many anti-allergy medications, which is why some of those cause drowsiness.

Your best bet would be to go to http://www.bestoverthecountersleepaids.com/ the site reviews such sleeping aid treatments.

Enjoy your trip !
References :
http://www.bestoverthecountersleepaids.com/blog/
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