Abstract: The present invention proposes novel salt compounds for use in the diagnosis or therapy of a patient as well as drugs, medical products, diagnostic compositions or blood products containing a salt compound according to the invention. The salt compounds according to the invention comprise the cation of a metabolisable basic amino acid and the anion of a metabolisable carboxylic acid or an anion of carbonic acid. Those salt compounds therefore have the advantage that they are fully metabolisable and thus do not adversely affect the electrolyte balance or the acid-base balance of the patient.