weight gain

The citilapram did not help very much for the depression I was having this summer so now I am trying lexapro.  However, the ability and lexapro seem to have other consequenses - weight gain.  I am so frustrated.  I do not want to gain any more weight.  I just lost weight about a year and a half ago and now I can feel it creeping back on.  It seems all I want to eat is carbohydrates.  Does anyone else have the same problem?  I don't know what to do.  Is there anything that does not have weight gain as a side effect?