Did I just eat all that? No, really. Is it gone?

I've gained 50 pounds on Zyprexa.  I was 125, and now I'm 175.  I'm tall so it doesn't look too bad, but still 50 freaking pounds.  How long will this go on? My doctor doubled a prescription of a drug I'm taking that's supposed to supress appetite,  and if that doesn't work I'll try a diet drug that I haven't tried yet because it causes anxiety, and works against an antipsychotic.