The only "remedy" I've tried is the Relief Band: a watch-like device that emits different levels of electric stimulation. It seems to work well, I've only used intensity levels 1 and 2.

More often than not, my nerves are at their highest before a flight. I've flown about 110 times since getting back on a plane after a 14 year lapse. Since then, I've never freaked out or thought the turbulence was at a level I couldn't handle (close a few times.) So either I've been lucky, can handle more than I think, or the odds are that a nightmare flight is yet to come.