Process for conditioning substances

The present invention provides a process for obtaining finely divided particles or material mixtures having a sub-particle size of 10 μm in a form that preserves their aerodynamic properties during processing, storage and use of the inhalation compositions. According to the invention, the material or mixture of materials is cut to particles of less than 10 μm, then conditioned by hydrotreated steam, finally the conditioned material or mixture is dried and the resulting 10 μm non-permeable particles are separated. By using the method, the physical-chemical characteristics of the dry product are advantageously changed, the treatments or mixtures of materials become technically more manageable and their therapeutic value is increased. ŕ