The instrument has a hand-piece (1) comprising an elongated body (11) with a housing (111) for housing a cylindrical support. One of the ends of the instrument comprises a driving unit (19) for rotatably driving a pharmaceutical product container and a perforating injection needle (5). An electronic syringe-driver (18) exerts the pressure during perforation in a controlled manner on a predetermined quantity of pharmaceutical product in the container inserted into the housing to prevent entering of perforation debris in an opening of the needle. An independent claim is also included for a method for perforating a dense tissue of a human or animal body and injecting a pharmaceutical product in a zone of the body accessible through the dense tissue.