It is described a new method for the preparation of pharmaceutical tablets carrying poorly soluble in water principle; this method allows to obtain tablets with fast and/or slow release of the active principle. The peculiar feature is the fact that the poorly soluble in water active principle (es: nifedipine) is treated with a surfactant, during the granulation phase or whatever during the preparation process; the obtained product, subjected to a compression, produces pharmaceutical tablets which show high bioavailability of the carried active principle. This procedure can be used to prepare polymeric matrixes (with modified release), formed by tablets with one or more layers. The procedure of manufacture and the characteristics of the new finished tablet are described.