i'm taking this medication because I'm Diabetic. Is it suppose to...

i'm taking this medication because I'm Diabetic. Is it suppose to have me gain weight? I'm also taking Diovan and Actos since this past May and I've notice the weight gain. I've been on Glyburide and Norvasc for quite sometime and it hasn't made me gain weight. Can these first 3 medications (Metformin, Diovan and Actos) be substituted with medications that doesn't make me gain weight. I'm reaching close to 160 lbs. when I weighed 143 lbs. for the longest time and was doing good losing more. Thank you, Val ******