Kirk Lewis said in a statement Bing, 68, spent Thursday night at Henry Ford Hospital and has a "commonly diagnosed, non-life-threatening condition," the Detroit Free Press reported.
"He continues to rest comfortably, and a decision will be made later today regarding his release," Lewis said. "The mayor is alert, upbeat and tells me he's ready to return to the office."
Bing was hospitalized Thursday after suffering discomfort following a morning visit to a dentist.
WJR-AM Radio, Detroit, reported Bing had said Thursday night he thought he might have colitis, or inflammation of the colon, or large intestine, the Free Press said.
Bing told the radio station he was doing well and expected to be released Friday.
Bing had said in January he weighs just 10 pounds more than he did when he played pro basketball and that he plays tennis and avoids junk food, the Free Press said.