"i have only been on belviq for 1 week. i&#039;m not sure if i have lost any weight yet. i am experiencing many side effects. bad headache, slightly dizzy, very tired (napping almost daily), and stomach issues (heartburn &amp; diarrhea). i&#039;m giving it 6 weeks and then i will decide what to do. i&#039;m hoping the side effects go away within another week."