Hi , I Am Currently Taking 150mg Of Effexor And

Hi ,
I am currently taking 150mg of Effexor and have started taking xenical. Does the xenical affect the absorption of the Effexor? If so, when should I take the Effexor as you have to take it with food and you also take the xenical with food?
Also, I would like to switch to Wellbutrin from Effexor as I have put on weight with Effexor. Does Wellbutrin work the same way as Effexor?

Thanks,
Mel