The present invention relates to a new process for producing nanoparticles laden with active ingredients, and to the use thereof as medicaments. The process for producing nanoparticles comprises the steps (a) dissolution of at least one active ingredient and at least one polymer in an organic solvent, (b) mixing the solution prepared in step (a) with an aqueous phase, (c) evaporating the organic solvent, (d) purifying the nanoparticles laden with active ingredient obtained in step (c) by means of dialysis against aqueous dialysis solution containing the same active ingredient.
