Rep. Jesse Jackson Jr., who has been on a lengthy medical leave from Congress because of bipolar disorder while also facing separate federal investigations, resigned from Congress Wednesday, citing health problems.

“The constituents of the (2nd) District deserve a full-time legislator in Washington, something I cannot be for the foreseeable future. My health issues and treatment regimen have become incompatible with the House of Representatives,” Jackson wrote.

Jackson’s resignation comes on the heels of the election where his constituents re-elected him to a ninth term. According to state law, Illinois Gov. Pat Quinn will declare Jackson’s seat vacant once the congressman gives official notice of his resignation, and there will be a special election to fill the seat.

Jackson is under a House Ethics Committee investigation into his dealings with imprisoned ex-Illinois Gov. Rod Blagojevich, and reports have also surfaced that there may be a new inquiry into possible misuse of campaign money.