What type of kinetics is alcohol metabolism characterized by?

Alcohol metabolism is primarily characterized by zero order kinetics. This means that the rate of alcohol elimination from the body is constant and does not change with the concentration of alcohol in the bloodstream. Unlike first order kinetics, where the rate of elimination is proportional to the concentration of the substance, zero order kinetics implies that the body can only metabolize a fixed amount of alcohol per unit of time, regardless of the amount present.

This property can be attributed to the saturation of the metabolic enzymes responsible for breaking down alcohol, particularly alcohol dehydrogenase and aldehyde dehydrogenase. Once these enzymes are saturated, an increase in blood alcohol concentration does not lead to an increase in the metabolic rate. Thus, the metabolism occurs at a constant rate (typically about 0.015 grams/deciliter/hour in average individuals), making zero order kinetics the correct choice in this context.