Hi I'm Bipolar I've Been Taking Ambilify For A Few

Hi I'm bipolar I've been taking ambilify for a few months now and I've Gaines thirty pounds on the pills .now I've switched to the injection. I would like to know if this drug caused my weight gain in anyways, and if the injection will cause me to gain more weight then the pills itself, what would be the best drug I take for bipolar so I do not gain any weight on it ,please help thank you.