In new drug development studies or clinical trials, zero-dose control is needed in general to determine the lowest dose level for a new drug which can act with our bodies. When the lowest dose level compared with zero-dose control has significant difference in effect, it is referred as minimum effective dose(MED). We propose, in this paper, parametric sequential test using updated control to identify the minimum effective dose(MED) level. Monte Carlo Simulation is adapted to examine the power and experimental significance levels of the proposed method with other methods.