<P> The first point along the graph where a response above zero ( or above the control response ) is reached is usually referred to as a threshold - dose . For most beneficial or recreational drugs , the desired effects are found at doses slightly greater than the threshold dose . At higher doses , undesired side effects appear and grow stronger as the dose increases . The more potent a particular substance is , the steeper this curve will be . In quantitative situations , the Y - axis often is designated by percentages , which refer to the percentage of exposed individuals registering a standard response ( which may be death , as in LD ) . Such a curve is referred to as a quantal dose - response curve , distinguishing it from a graded dose - response curve , where response is continuous ( either measured , or by judgment ) . </P>
<P> The first point along the graph where a response above zero ( or above the control response ) is reached is usually referred to as a threshold - dose . For most beneficial or recreational drugs , the desired effects are found at doses slightly greater than the threshold dose . At higher doses , undesired side effects appear and grow stronger as the dose increases . The more potent a particular substance is , the steeper this curve will be . In quantitative situations , the Y - axis often is designated by percentages , which refer to the percentage of exposed individuals registering a standard response ( which may be death , as in LD ) . Such a curve is referred to as a quantal dose - response curve , distinguishing it from a graded dose - response curve , where response is continuous ( either measured , or by judgment ) . </P>
the threshold on a dose-response curve is the
the threshold on a dose-response curve is the
first point along the graph where a response above zero ( or above the control response ) is reached
first point along the graph where a response above zero ( or above the control response ) is reached