It's funny that you mention this. I've gained just about 40 pounds since I started taking the seroquel. It's been hard to adjust to because I was underweight for my entire life up to this point, and now I'm officially overweight. This is one thing my husband is not supportive with. He's very upset with me, because he says a medication can't make you gain weight unless you've increased your caloric intake, which may be true. Three hours after taking the seroquel, I start craving sweets with such intensity... and I've never been like that with food before. So my husband says the weight gain is a self-discipline issue and that I should be ashamed of myself.
I'd start exercising, but there's a serious hereditary disease that runs in my family (my older sister died from it), and the number one thing I've been told by doctors is that I need to be extremely careful not to overexert myself. So I do a lot of walking, but I'm not really supposed to do more than that, because I may end up in a wheelchair within the next 20 years as it is, and I don't want to make that happen any sooner. The disease is Mytochondrial Myopathy, which is fairly rare and not much is known about it yet.
So yeah, when it comes to the weight gain, I'm kinda screwed. Seroquel is the only medication that's ever helped me, and I can't do much exercise, and I crave sugar CONSTANTLY. It sucks.