Marc Washington, 64, was last seen near 645 S Central Ave after leaving Loretto Hospital on Monday, police said.
Marc is about 5 feet and 9 inches tall and weighs around 120 pounds. He has brown eyes and grey hair.
Marc was last seen wearing a red Bulls hat, beige shirt and black jacket. He has difficulty walking and uses a colostomy bag, police said.
Anyone with information on where Marc might be is asked to contact the Chicago Police at 312-746-8255.