Take it from an experienced bizniz frequent flyer: On the day of your flight or the day before, go to your regular MD. tell him your flying and want a 3CC shot of B12 to help jet lag and reduce nervous tensions. If there are no reasons not to have it this should do it... He'll give you 3 or 2 CC While your away take 2000 B12 each day I do it almost every month when there is at least a 6 hours time change. I dont find it necessary on North South flights as no time change, but still take 2000 a day anyway to keep my mind sharp with the clients. By the way....Pilots and cabin crew also use it Chuck CG for Joyce