Calcium-containing compounds have been at least partly film-coated and/or granulated with a water-soluble substance and a water-soluble polymeric substance and use of such coated compounds in pharmaceutical compositions. The at least partly film-coated and/or granulated calcium-containing compounds have proved suitable for the preparation of tablets having a very high load of elemental calcium and a conveniently small size. A drug load of about 96% or more is obtained in tablets of the invention that have sufficient mechanical and organoleptic properties.