There are definitely dr's that are bipolar but I believe you have to self report to be liscensed. Mark Vonnegut was diagnosed as schizophrenic went into inpatient then later after recovery as bipolar and then went to Harvard med and is a leading pediatrician...his second book deals with becoming a dr.

I'm sure it's different from state to state though since the liscensing is different. Here you can't even get a drivers liscense if you've been involuntarily committed.