Well most schools I've seen don't technically "require" a certain GPA, but if the schools you are researching do, I would contact the school directly to see if there is wiggle room with the policy. If there is wiggle room, or your school doesn't have a minimum requirement, I would start putting together an "alternate transcript". This would mean that you should take some business type classes at a local college, junior college, or internet classes with a top school, and make sure to get A's! Starting to put together a 3-4 classes like this will shows that you can handle the riggors of classes, and your low GPA will continue to fade into the background.
Classes would include Statistics, Accounting, Economics, Calculus, etc...
Then in your essays I would talk about your disorder, or challenges you've faced, and how that attributed to your GPA. And then show what you've learned from that, and how you're challenges will help you face your future challenges in business school.
A top score GMAT wouldn't hurt!

Good luck
_________________