The Dose-Response Relationship

Understanding the dose-response relationship is essential for multiple scientific studies and disciplines such as pharmacology, chemistry and biology.  In particular, dose-response relationships are studied prevantly in Toxicology closely studies the various predictions and implications of dose-response relationships. The Dose-response relationships are so crucial to the field of toxicology simply because a wide variety of toxic reactions (responses) exist, which correspond to the amount or concentration of a toxic substance (dose) administered to an individual.  Since the human body is so intricate and connected, dose-response relationships must be studied carefully. The Merck Manual importantly notes that "the response to concentration [of dose] may be complex and is often nonlinear".

Before recording data and constructing the curve of dose-response relationships, one must first understand the relationships' implications. Extension Toxicology Network (EXTOXNET) define two implications: that there is almost always a dose in which no response occurs or can be measured below a certain level and that any further increases in a dose or concentration will not result in any increased effect once the maximum response is achieved. These two implications are helpful in defining the threshold of a fatal response for any given toxic substance.

Two types of curves can be constructed to further understand the potential hazard of a given toxic substance: one that displays and describes the responses of a dose to an individual, and one that displays and describes the responses of a dose to a population.  For both curves, the dose is represented on the x-axis as a function of time and the response is represented on the y-axis. Additionally, both curves most always form in a hyperbolic fashion. The visual representation of dose-response relationships in a mathematical form allow toxicologists to define the threshold of responses for a toxic substance more clearly.

The development of dose-response relationship studies have been extremely useful for administering and prescribing drugs in medical environments.  By understanding dose-response relationships, millions of lives have been saved and improved. Toxicologists will continue to utilize curves and dose-response experiments to prevent the detrimental consequences of toxic substances.  

These pictures show warning labels of a bottle nail polish remover and Bacardi rum.  These warnings were most likely based on a population dose-response curve rather than an individual dose-response curve.