The method introduces additives into a flowing melt or fluidized metallic/ceramic powder media in a pulsed high pressure manner. The nozzle needle of at least one nozzle is variable and highly precisely moved for the introduction by means of a device and in such a way that additive is dosed exactly in relation to the volume flow of the medium. The pulsating additive stream is injected into the flowing medium by at least one well-aimed nozzle opening. The additives are dosed by means of a pressure that can be variably adjusted by pulse width and pulse frequency. The desired homogenous distribution is obtained by the penetrating injection jet.