Will I lose weight on Wellbutrin the 2nd time around?

The first time I took it, I was taking 300mg of the generic for around 2 years. I had lost about 10 lbs. Eventually I tapered off it and then stopped taking it completely and gained 25 lbs! (I had also started birth control around that time, so that may be part of the reason for my rapid weight gain).

I plan on going back on it and I want to know if I can expect the same weight loss effects or will my body already be used to it?

Ps. I've been off of it for 3 weeks and my Dr said I can go back on it once it's been a month.