I've noticed after surgery twice that vicodin seemed to be a mood stabilizer for me. But I'd never, ever try to use it as such because it is too dangerous and there are way too many reasons not to consider it. I've joked about it with my pdoc that it figures that the one med that works isn't something we can use. It makes me afraid of taking pain pills because while I don't think I'd cross a line many others have thought that too just before crossing a line.