1. Cortisol secretion inhibition in 70 healthy individuals was followed-up, after the peroral application of dexametason 2,5 mg/24. Plasma cortisol, with initial values of 18,8 +/- 0,64 mkg/100 ml was inhibited to 5,7 +/- 0,21 mkg/100 ml. The decrease is with 69,7 per cent of the basic level. 2. The indices for normal values were drawn as well as a positive hormonal response to dexametason: initial level between 6,3 and 29,4 mkg/100 ml, cortisol decrease at least with 4,8 mkg/100 ml plasma and the plasma cortisol level after 2,5 mg dexametason--under 9,9 mkg/100 ml. 3. In case of hormonal response absence to dexametason those three indices were not observed. The hormonal response is disturbed if the decrease is under 4,8 mkg/100 ml or the inhibitory level does not reach the values under 9,9 mkg/100 ml plasma.