How does zero order drug kinetics differ from 1st order?

Zero-order drug kinetics is characterized by the elimination of a constant amount of the drug from the body per unit time, regardless of the drug's concentration. This means that the rate of elimination is constant, leading to a linear decrease in the amount of the drug over time. In contrast, first-order kinetics involves drug elimination that is proportional to the drug's concentration; higher concentrations result in faster rates of elimination.

In zero-order kinetics, since the rate of elimination does not depend on the concentration of the drug, it remains steady until the drug is completely cleared from the system, which can lead to potential accumulation if dosing is not adjusted appropriately. This is particularly important for drugs that follow zero-order kinetics, as an understanding of the elimination process allows for better management of therapeutic levels and potential toxicity.

Understanding these differences is crucial in pharmacology, as it influences dosing schedules and the monitoring of drug levels in patients.