Disclosed herein is a method of making a powder for inhalation comprising: a) a first step of mixing a force-controlling agent with particles of one or more pharmacologically active materials in order to obtain a mixture wherein the particles of said force-controlling agent are disposed on the surface of the active particles as either a particulate coating, or as a continuous or discontinuous film； and then b) an optional second step of mixing or blending said mixture with a carrier material； wherein the mixing in step a) is achieved by one or more of the processes of sieving, mixing or blending the particles of one or more pharmacologically active material and particles of force-controlling agents； wherein the mixing or blending is carried out in a diffusion blender, tumble blender, bin blender or conical blender, or a high shear mixer； and wherein the force-controlling agent is selected from the group consisting of titanium dioxide； aluminium dioxide； silicon dioxide； starch； and salts of fatty acids.
