6-ethyl chenodeoxycholic acid, or obeticholic acid, is indicated in the treatment of primary biliary cholangitis as monotherapy in patients with intolerance to usual treatment or in combination with ursodeoxycholic acid (UDCA) in adults [1]. Deoxycholic acid, one of the natural secondary bile acids, is used in order to emulsify fats for absorption and as a treatment component its role regards the prevention dissolution of gallstones [2]. a b Thermoanalytical curves of a) 6-ethyl chenodeoxycholic acid and b) deoxycholic acid In order to properly estimate the values of the activation energies for the two tested compounds, a series of isoconversional methods (Kissinger–Akahira–Sunose, Flynn-Wall-Ozawa and Friedman) were chosen and five different heating rates were used for the analysis: β=5, 7, 10, 12 and 15 °C min-1 [3]. The obtained results were processed using the NPK method in order to objectively separate the physical and chemical processes that participate to the thermal degradation. A kinetic evaluation is presented regarding thermal stability.