The Frankston railway line is experiencing major delays after a woman was found lying on the tracks near Highett station.

The woman was not hit by a train, but is believed to have been under the influence of drugs.

A spokeswoman for Metro said trains were halted while police and ambulance attended the scene.

The woman was taken to Monash Medical Centre.

Trains are resuming but there are delays of up to 30 minutes while the backlog of trains is cleared, the spokeswoman said.