Cannon said in a statement on the 92.3 NOW website that Friday was his last day hosting the two-year-old show, called Rollin'.
He said doctors had ordered him to cut back on his professional commitments and get more rest. He tweeted on Friday that doctors had found blood clots in his lungs.
The 31-year-old entertainer was hospitalised last month after suffering from what his wife, Mariah Carey, called "mild kidney failure".
Cannon said he'll continue to host his syndicated weekend show, Cannon's Countdown. He added that he will "look forward to contributing to 92.3 NOW whenever possible".
