Police are becoming increasingly concerned for the welfare of Michael Cullen.
Michael was reported missing from his home in the North Circular Road area by his family on January 9.
He was last in contact with his family at around 2pm on Tuesday.
Michael is 5”11 tall with dark hair and beard. He was wearing a green puffa jacket, grey jumper and black trousers.
A police spokesperson said: “We are appealing for Michael, or indeed anyone who knows of his whereabouts to contact us on 101, quoting reference number 622 9/1/18.”