My parents used to be terrified to flying, so they got temazepam from the doctor. It should knock you out completely, but coupled with the adrenaline from the fear, they sort of balance out so you're really drowsy.
What happened is that each time they flew, they got more and more used to it, and so they got prescribed less and less. When flying to Hong Kong last year (from UK, so that's a 13 hour flight (I think)), my mum went without any drugs, and my dad's prescription was about half of that that he used to use - neither or them had any problems throughout the flying.







