"i started taking phentermine on october 18, 2008. at that time, i weighed in at 263 lbs. i&#039;m 5&#039;10 so i carry weight very well. as of my weigh in yesterday (april 30, 2009) i&#039;ve lost 41 lbs. the only side effect that i&#039;ve had to deal with is insomnia; but over time, that has gotten easier to deal with. i&#039;d recommend this medication; however, i would also stress that the weight you put on wasn&#039;t put on overnight and therefore, won&#039;t come off overnight. slow and steady wins the race."