Question: how long does it take for bupropion to work for weight loss?
Answer: Another study, published in 2002 [3], also showed significantly better weight loss among those taking Wellbutrin. In this study, some were prescribed the usual 300 mg/day while others took 400 mg/day. Those taking Wellbutrin lost an average of 13 lbs (5.8 kg) in 12 weeks compared to 6 lbs (2.8 kg) in the placebo group.