What does the term 'elimination' refer to in pharmacokinetics?

In pharmacokinetics, 'elimination' specifically refers to the removal of a drug from the body. This process encompasses both the metabolic breakdown of the drug (biotransformation) into metabolites, primarily occurring in the liver, and the excretion of these metabolites or unchanged drug from the body, usually through the kidneys in urine or through bile in the feces.

Understanding elimination is crucial for determining a drug's duration of action in the body and its overall clearance, which influences dosing decisions and potential toxicity. This highlights the importance of elimination in managing pharmaceuticals effectively and safely within a clinical setting. The other concepts, such as absorption, distribution, and metabolism, while related to pharmacokinetics, do not accurately capture the meaning of elimination.