"i had to sell my physician on belviq. she was not 100% but came around and now refers to me as the guinea pig. had rough side effects up front but pushed through them. headaches, backache, constipation and nausea to name a few. lasted about 4 weeks. in the first week i had to force myself to eat.  i&#039;m 9 weeks in and down 25 pounds. realize i&#039;m content on 1100 calories. using myfitnesspal app. worried about keeping it off like everyone else. at 41 yrs. old, i thought my metabolism was gone. this medicine is a game changer."