Well, I do not have the MS, but flying is out of the question. For years, I was holding my head writhing with pain while everyone else was joyously celebrating the vacation, family reunion or whatever event we were going to attend. Every one kept asking me, "Well, why don't you just chew some gum, or hold your nose and blow lightly to clear your ears ?" They thought I was being a wimp, and I certainly could not understand why I had such a time with it. Until I was diagnosed with the TN - also, if my sinuses get stopped up or I have a cold, it is likely to set off an episode. I would assume that anytime there is more pressure in your head everything is compressed and increases the pressure on the affected nerve.