Very, very useful for traveling (ie. crossing the Atlantic) and helping with killer jet-lag! "Only" 4-stars since u really have to watch out: I learned the hard way: DO NOT take a "full pill". Try 1/4 pill FIRST...if after an hour, u need more, take another 1/4...etc. Depends on how bad your jet-lag is, but this stuff if GREAT and u can "dry swallow" on a plane if u have to or anywhere else water isn't available!