The present disclosure relates to a method for the preparation of a nanosuspension of at least one natural material, wherein the method comprises the steps of (a) providing at least one natural material having a particle size (D90) of less than 320 μm (b) dispersing said at least one natural material of step (a) in a solvent and (c) milling the dispersion of step (b) to a particle size (D90) of below 1000 nm. The nanosuspension is useful for the preparation of a medicament.