Just started adipex

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Ok so a year ago I weighed 170lbs...I'm 5'5. I weigh 150lbs now. I'm content where I'm at because I've always been a curvy girl...but I would like to lose maybe another 20 becuz I'd like to be comfortable in a bathing suit lol...and I love summer time and swimming! So today I started adipex...I know all the side affects and dangers...I plan on only using this one bottle and not getting anymore...I do not want to become dependent on it. I'm active and I watch what I eat...I splurge one day a week other than that I'm not crazy healthy on food choices but I only take in 1,200 calories a day and most of that being healthy choices with maybe a treat. Today all I've noticed is very dry mouth so I've drank a ton of water and I'm a lil jittery...but on and all I feel great! I guess I'm looking for advice from anyone whose tried adipex. How much weight should I expect to lose in the two months this bottle will last...I've kept 20 off for over a year now.