Clearance-modellen: fysiologische modellen

Drug clearance features irreversible drug removal from any organ in the body.

Physiological models determine clearance through an individual organ, defined by the drug fraction eliminated per unit of time from the blood volume of that organ.

Organ clearance can be defined as the product of the blood flow to the organ and the extraction ratio E.

Here, E indicates the organ's ability to eliminate the drug. It depends on drug concentrations in the blood entering and exiting the organ.

The extraction ratio can range from 0 to 1, indicating negligible to 100% drug removal. For example, an E value of 0.25 signifies that out of the total incoming drug, 25% is removed by the organ.

As per the model, organ clearance varies with changing blood flow and the organ's extraction ability. In contrast, total clearance refers to a constant fraction of the blood volume from which the drug is continuously removed over time.