Wow! 40 pounds is super!! Babe, you do not need it as a maintenance drug. During the time on it is the time to take the steps necessary to buy, prepare and eat healthy foods. I know it's not an easy task, but it's absolutely necessary for success. If you do not, you'll be taking this same ride every year for the rest of your life. A circle of gaining, losing, gaining, losing...NONONO.
Call your regular doctor and ask for 1 month's medicine, then give it eveything you've got. Pull out all the stops!! LET'S GET 'ER DONE!!