Borosilicate glasses, preferably for use in the pharmaceutical sector, are provided. The borosilicate glasses are outstandingly suitable for the use as pharmaceutical primary packaging, such as phials or ampoules, since the aqueous or water-containing medicaments kept in the containers do not attack the glass significantly, and so the glass releases no, or only few, ions. The borosilicate glasses have the following composition in % by weight or consist thereof: SiO271-77; B2O39-12; Al2O35.5-8; Na2O6-8; K2O0.1-0.9; Li2O0-0.3; CaO0-1.5; BaO0-1; F0-0.3; Cl-0-0.3; and MgO + CaO + BaO + SrO 0-2.