Abstract: By a theoretical investigation of simulated nonisothermal data, the estimates for shelf life and activation energy obtained by exponential and other nonisothermal heating models were statistically evaluated and were compared with those obtained by the isothermal method under various conditions. Results indicated that under the same experimental conditions, the estimates obtained by the exponential heating model were significantly more accurate and precise than those obtained by the linear, reciprocal, and logarithmic heating model. The estimates obtained by the isothermal method were somewhat more accurate and precise than those obtained by the exponential heating model. However, the experimental period needed by the isothermal method was about 5 times longer than that needed by the exponential heating model. Results also showed that in each of the heating models, the estimates would be more accurate and precise by increasing the final degradation of drugs, chan