I started taking phentermine about 3 weeks ago. And I can tell where I have lost weight. I am 17 years old and I am overweight. About 260 and I havent really started excercising yet. I have been drinking water. The pills really curve your appetite. I used to eat a lot all day eat breakefast, luch, when I got home from school, and then dinner. Now I only eat 1 or 2 times a day and its not much. It gives you tons of energy. You feel like you need to be doing something active all the time for me its cleaning the house til its spotless. I got mine online and payed 100.00 a bottle for 100pills its about a 3month supply. I got introduced to it from a neighbor who is my moms age but used to weigh the same much as me and now in a little over a year so is 170 and still taking the meds. So yes it does work. The only thing it does as far as side effects is it makes your mouth really really dry so I keep water with me all the time.