Solid composition comprising (a) an anionic surfactant in combination with a water-soluble and basic polymer, or (b) a cationic surfactant in combination with a water-soluble and acidic polymer, and (c) at least one poorly water-soluble pharmaceutically active ingredient, and solid or liquid dosage forms, especially tablets, coated tablets, capsules or suppositories or aqueous solutions comprising the solid composition. The surfactant/polymer system is soluble in water and solubilises the active ingredient so that good bioavailability with therapeutical quantities may be attained. Aqueous solutions are suitable for nasal, parenteral or ophthalmic treatments.
