The invention relates to the medical field, in particular, to medications for treating arthropathies. The medication is based on a Sodium salt of chondroitin sulfate (CS), a mucopolysaccharide produced from animal tissues. The medicinal product influences metabolic processes in connective tissues, including those in cartilages, promoting and normalizing the biosynthesis of glycosaminoglycans. The essence is that the medication is produced from a chondroitin sulfate Na-salt substance having an intrinsic viscosity (? of 0.01-0.15 m3/kg and free from peptides. The result is that a medication is produced that meets the requirements applicable to medicinal products containing mucopolysaccharides, in particular, chondroitin sulfate, while being substantially free from such side effects as painfulness of injections, occurrence of indurations and hemorrhages in the injection area, and, occasionally, infiltrates.