Relatives say 79-year-old William Cahill left his home and has not been heard from since last week.
Neighbors say they saw Cahill getting into an unknown car on Friday, August 10th around 5:00pm.
He is described as a white male, around 5'7" tall, with gray hair, brown eyes, weighing around 230 pounds. He was last seen wearing a white t-shirt, blue jeans and thick glasses.
Relatives say he was carrying his wallet and cash, but all of his medications were left behind. They say he is in the early stages of dementia and has other health issues that require medication.
Police say there has been no activity on his accounts.
Anyone with information is asked to contact Collingdale Police at 610-586-0502.