Dose-response curve
In science , dose-effect curves graphically describe the relationship between the administered dose of a measure and the resulting effect. This effect can relate to an individual or to a group of individuals. A distinction is made between monotonic and non-monotonic curves. The dose-effect curve is used, for example, in pharmacology , ecology and environmental economics
Dose-response curve for an individual
On the abscissa , the dose (quantity) (at a is concentration-response curve , the concentration) was applied - usually in logarithmic form, on the ordinate the effect in percentage. The maximum effect of a full agonist is considered 100%. Due to the logarithmic plot on the abscissa, the course of the curve is usually sigmoidal ("S" -shaped). Three parameters can be read from such a dose-effect curve:
- the potency or potency . It indicates the minimum doses (or concentrations) of an active ingredient that are required to achieve a desired effect.
- the maximum effect of an active ingredient (strictly mathematically, the curve asymptotically approaches the maximum effect ). The maximum effect is also a measure of the intrinsic activity of an active ingredient.
- The steepness of the curve provides information about how broad the spectrum is between a minimum measurable effect and the maximum effect of a drug.
Such a dose-response curve represents an integration into which the pharmacokinetics , the concentration-binding curve and the binding-effect curve are included. If the dose-effect curves of several drugs are plotted in a diagram, their properties can be compared with one another.
Dose-response curve for a group of individuals
A dose-response curve can also describe the effect of a dose on a group of individuals. Here, too, the dose is plotted on the abscissa , usually in logarithmic form. The percentage of the individuals in the group who show the desired therapeutic effect at the corresponding dose is plotted on the ordinate. Such a semi-logarithmic plot in turn results in “S” -shaped (sigmoidal) curves.
The effective dose (effective dose) can be read from such a dose-response curve. It indicates the dose at which a certain proportion of individuals shows the desired therapeutic effect. The mean effective dose (ED 50 ) indicates, for example, which dose leads to the desired therapeutic effect in 50% of the individuals. A dose-effect curve can in a corresponding way also show the proportion of individuals for which a dose has lethal consequences. Analogous to the effective dose, the lethal dose can also be defined (around LD 50 ).
Since the method of application is identical, both dose-effect curves (for effective dose and for lethal dose) can be entered in a coordinate system. The therapeutic range of active ingredients can then be estimated from the diagram .
Individual evidence
- ↑ Pete Myers, Ph.D. and Wendy Hessler: Does 'the dose make the poison?' (English)
- ^ Roman Bauer: Ecological Risks from Energy Conversion Processes in Power Plants . In: Alternative options for energy policy . 1978, p. 91-104 , doi : 10.1007 / 978-3-322-83864-3_3 .
- ^ Mendelsohn, R., & Orcutt, G .: An empirical analysis of air pollution dose-response curves . In: Journal of Environmental Economics and Management . tape 6 , no. 2 , 1979, p. 85-106 , doi : 10.1016 / 0095-0696 (79) 90022-6 .