go potty
1. To become irrational, crazy, eccentric, or addlebrained. Primarily heard in UK. I'll end up going potty if I have to work in this cubicle for one more day!
2. To become very excited or enthusiastic (about something). Primarily heard in UK. People are going potty for the new art exhibit.
3. To urinate; typically said of, to, or by young children. My three-year-old has started going potty all by herself!