Cheruiyot was listed in stable condition at the Northwestern Memorial Hospital where doctors said his condition was not serious.
The Kenyan was being kept overnight so they could monitor his injuries which included minor internal and external bleeding.
"He was a little confused after the race," Cheruiyot's manager Frederico Rosa told reporters.
"He couldn't remember what happened. He has a lot of pain in the head. He didn't remember how he fell down."
Cheruiyot won in a time of 2hr 07min 35sec. However, his joy was short lived when he slipped on a corporate bank logo seconds before the reaching the tape.
He still managed to cross the finish line because his feet were flung forward as he skidding under the ceremonial banner. At the same time he smacked the back of his head on the ground.
"Luckily for him, he slipped forward," race referee Pat Savage said. "I've never seen that happen before."
Berhane Adere crosses the line to
win the women's marathon
Cheruiyot lay on the ground for several minutes before being taken away from the finish area in a wheelchair.
A bloodied Cheruiyot asked race officials, "Did I win the race?" as he was being transferred to a waiting ambulance.
Fellow Kenyans Daniel Njenga (2:07:40) and Jimmy Muindi (2:07:51) were second and third respectively.
Njenga initially thought he had won.
"After (Cheruiyot) fell down, I thought maybe I am the one who won the race," Njenga said.
"Somebody told me I am No. 2. I have nothing I can do. I have to accept it."
This was Cheruiyot's second victory in a World Marathon Majors series this year. He also claimed victory in Boston earlier in April.
His two wins earned him a total of 50 World Marathon Majors points, and a 25 point lead in the series over Felix Limo and Haile Gebrselassie.
Limo was the 2005 Chicago champion, but had to withdraw from this year's race due to a back ailment.
The women's race was won by Ethiopia's Berhane Adere in 2:20:42 with Russia's Galina Bogomolova (2:20:47) and Australia's Benita Johnson (2:22:36) completing the top three.
Romania's Constantina Tomescu-Dita dropped to fifth after leading the first 34 kilometres (21 miles).