i too have suffered vertigo. went to a dizzy specialist at ucla, westwood, california who showed me an excercise that anyone can do. you drop your head off the side of the bed while on your back. slowly turn your head from one direction all the way to the other direction. or perhaps it is lie on your side and do it....i am sure you can find a link and a video on line, my kaiser doctor friend sent it to me one time. the ucla doctor said it was hormonal in my case, the kaiser dr didn't think so. i have snapped my neck many times, boogie boarding, snow boarding, skiing etc. but i thought it had something to do with being dehydrated which is why someone on here saw a connection between caffeine and vertigo, caffiein being a diuretic. my own theory is that the dehydration dries up the liquid in the ear and somehow these particles get in the wrong place. moving your head when you feel ilke throwing up and cannot move is HARD!!!! and i had to do it more than once but it worked and i spaced it out cause i was sooo sick. the doctors agree that moving the head, and thus the ear relocates the loose particles in the ear. i know this is a great discovery for many people but perhaps won't work for everyone. don't forget to always stay well hydrated!!