Can I buy valium in turkey without a prescription? i have along flight and want to sleep. thanks.
Officially: Probably not.
But my parents told me hordes of tourists are always storming the airport pharmacy in Antalya buying prescription drugs like (real) Viagra, antibiotics and sleeping pills - I doubt that anyone of them has a prescription.

You can buy alcohol legally, just as good at helping you sleep.
#1, Not sure Viagra would help you go to sleep. Perhaps it stops the guy in front pushing his seat back onto you ;-)
I am not sure that you want valium. Its effect lasts longer than most long flights. Look for lorazepam (ativan) which only lasts about 6-8 hours.
Not sure where you are coming from but perhaps there is someplace along your journey where you could actually see a physician and get a prescription.
Ruth
