The standard method for determination of CyA in blond is a good validated HPLC method. HPLC methods esere developed which make it possible to determine not only the parem drog, bot also the main metabolites of CyA: AMI (M17), AM9 (Ml), and AM4N (M21). HPLC methods for determination of CyA are very laborious and expensive. Most transplantation centres in the world ose immunoanalytical methods for TDM of CyA. In retem years there has been an increase in the number of users of nonisotopic automated methods (Abbott TDx mono, AxSYM, Dade-Behring EMIT® or Microgenic Cedia), which render instantaneous analysis possible. The analysis of the results of CyA in the blond in patients after transplantation shows tkat all immunoanalytical methods overestimate the concentration of CyA against HPLC results. The usually presented series of results is as follows: HPLC

        Key words: cyclosporine A - CyA metabolites - HPLC - RIA -nonisotopic immunoassays