And the physicians and PhDs argue that the regular nightcap doesn't actually help you sleep; it does the opposite.
"...alcohol makes it hard for you to stay asleep and sleep well....research suggests that it loses any benefit as a sleep aid within just a few days... a few nights of regular imbibing, your body builds up a tolerance to alcohol's effects.... Hours later, when your body has mostly metabolized the alcohol, your sleep becomes fragmented, and you're prone to frequent wakings..."
If you carry an ipod/iphone/mp3 player, you might try one of the many available trance tracks available for inducing sleep. I tried one for several weeks and it (1) made me very sleepy and (2) gave me unusually peaceful sleep.
I can't explain it, except that it changed the nature of the thoughts I had before going to sleep. With the track, my thoughts were not my usual review of the day and preparation for tomorrow (which is actually bad stuff to think about in bed). Instead, my thoughts followed the random and illogical wanderings of the trance tape, and post-trance dreams were innocuous and peaceful.
That said, what I actually use on the trail is Zyrtec, which helps cut the dust allergies I have, and also makes me sleepy. Zyrtec doesn't do anything for my wife so it must be an individual thing.