I took Paxil for 7 years and had gained a lot of weight during that time. I work in an office so I do a lot of sitting and at that time was eating a lot of fast food so I just figured it was my unhealthy lifestyle that made me gain the weight. However, when I got off the Paxil, I started losing weight like crazy. I hadn't started exercising or anything, I just got off the meds. I lost 50 lbs! So, I would say that yes, it does contribute to weight gain. Of course, all those greasy hamburgers didn't help me at all ;) but I think if I lost that much just by getting off it, some of the weight must have been from the meds.