John Wrenn Cook, who is believed to be suffering from dementia or some other cognitive impairment, was last seen at 2016 Ridge Road in Clayton.
He is 5 feet 10 inches tall, weighs 165 pounds and has short brown hair and hazel eyes.
Cook, 27, is thought to be wearing blue jeans, a green T-shirt and tennis shoes.
It allows caregivers and nursing homes to report a person missing. In the past, only a family member could report an adult missing.