"i am 25 years old. i have been taking phentermine since june 19, 2008.  i started out at 5&#039;4 and 254.5 lbs.  my last doctors visit was friday july 25 and so far i have lost a total of 36.5 lbs.  this pill is great but it helps you become stronger towards the problem and if you exercise you have a better chance of not gaining all the weight back.  the doctor told me that patients generally lose about 14 lbs the first month 12 the second and about 8 the third."