A medication delivery device includes a housing, a door coupled to the housing and moveable between a closed position and an open position. The door permits insertion of a medication container, containing liquid medication, into the housing in the open position. A door opening mechanism is coupled to the door. A push member is axially moveable between a retracted position and a non-retracted position and located external to the medication container. The push member enters the medication container and pushes the liquid medication out of the medication container. A lock mechanism is coupled to the door opening mechanism and prevents opening of the door when the push member is in the non-retracted position inside the medication container, wherein the lock mechanism automatically unlocks the door opening mechanism when the push member is in the retracted position.