"i&#039;m on day 6 of phentermine, only taking half of the 37.5 and start my whole pill tomorrow. so far so good, i don&#039;t have a ton of energy but i&#039;m having to force myself to eat because i have no interest in food (which is really new for me). i am down 6 lbs in 6 days and am yet to hit the gym, i am following a low cal diet from my nutritionist. the only down fall is i have a really hard time getting to sleep, but i wake up feeling like i got a ton of sleep so either way."