| abstract |
Injectable X-ray contrast media comprise an aqueous solution of at least one sodium salt of an iodinated organic acid, which solution contains calcium and/or magnesium ions. Specified contrast agents are sodium metrizoate; diatrizoate; iothalamate; 3, 5-dipropionylamido-2, 4, 6-triiodobenzoate; N, N1-di(hydroxyethyl)-3, 5-diacetamido-2, 4, 6-triiodobenzoate; 3-acetamido-2, 4, 6-triiodobenzoate; 3-acetamido-5-propionamido-2, 4, 6-triiodobenzoate; and iodo-methane sulphonate. Calcium and magnesium ions may be added as X-ray-in-active salts, such as the chlorides; or as salts of radio-opaque iodinated organic acids. Alternatively, aqueous solutions of these acids may be neutralized with mixed sodium and calcium and/or magnesium salts. Other substances present may be chelating agents (ethylene diamine and tetra-acetate) and buffers (sodium biphosphate). The Ca and Mg ions are said to improve the physiological compatibility of the contrast media. |