dose response, a range of doses over which response occurs. Doses lower than the threshold produce no response while those in excess of the threshold exert no additional response. The shape of the curve is usually hyperbolic when plotted with linear axes and gives a sigmoidal curve when response is plotted versus the log of the dose. Beneficial drug responses are typically plotted on separate dose response curves. Because the dose response and the chemotherapeutic index can overlap to some degree and may have different slopes, the margin of safety is often considered to be a better index.
