Police are appealing for public assistance to help locate 18-year-old Johnny.
Johnny was last seen in Brockwell Crescent, Manor Lakes February 21 at 6pm, he was dressed in a grey jumper and black track pants.
Police have concerns for Johnny as he has difficulty communicating verbally and a medical condition that requires medicine.
He is known to frequent Wyndham Vale, Manor Lakes, Werribee, Geelong and Melton.
Anyone who sights Johnny is urged to call Triple Zero (000).
Anyone with information is urged to contact Werribee Police Station on 03 9742 9444.