Congressmen Bobby Rush and Danny Davis visited Jackson at his Washington home Monday for about an hour.
Rush tells The Associated Press they decided to visit after talking with Jackson's family. Rush said Monday that Jackson was en route Minnesota's Mayo Clinic, which released him last month following treatment for bipolar disorder.
Jackson's father, the Rev. Jesse Jackson, said Sunday his son would return to Mayo for a checkup but might stay longer.
A Mayo spokesman says Jackson isn't a current patient.
Jackson hasn't said when he'll return to work. He faces re-election Nov. 6.
Jackson's first communication with voters since June was a weekend robocall asking for patience.