Police are appealing for public assistance to help locate Jackie Stephens.
The 18-year-old woman was last seen at a Dandenong address on 15 November.
Police hold concerns for Jackie as she has a medical condition which requires on-going treatment.
She is known to frequent Dandenong, Springvale or the Caulfield areas.
Anyone who sees Jackie or has information on her whereabouts is urged to contact Dandenong police on 9767 7444.
