Unfortunately the issue is not gaining what you lost back. I lost about 15 pounds in 3 months with no exercise on phen. My doctor would only prescribe for 3 months at a time and it basically stops works even with an increased dose. After those 3 months, I gained about half back, went back on the pills, lost very slowly and then when those 3 months ended, gained everything back over the course of a year. I've been extremely stressed though with a baby and full time work so wasn't very disciplined while off the pills.

Hard to say. Do you have some kind of a metabolic issue (guessing that's whyt he doctor prescribed it).

I weigh 175 pounds and am 5'8 (and some change). I am hoping to lose 40 pounds and get down to 135 pounds.

My doctor prescribed phentermine and I took my first pill today. Assuming I don't experience any harsh side effects, how long do you think it will take me to lose 40 pounds?

I do not want to be on diet pills for the whole journey but definitely think my body needs a jumpstart.

I know the 1-2 pounds a week average for regular diets but was curious to see what your opinion might be on a few months on phen and a few months without it and what that timeline might look like?