Is it true that Zydis may be safer from that standpoint?

I am taking it with Metformin this time, but am confused as to what exactly it helps prevent. At the hospital they told me that Metformin prevents weight gain, but my internist said that it would only prevent diabetes (I mean, that is important enough, but I also would like to halt weight gain).

I could not tolerate Topamax.

What other options are there?