What is metabolism in the context of pharmacokinetics?

Metabolism in the context of pharmacokinetics refers to the chemical alteration of a drug by the body. This process usually occurs primarily in the liver, where enzymes transform the drug into a more water-soluble compound, facilitating its excretion from the body. Such alterations can lead to either the inactivation of the drug or its conversion into active metabolites that may have therapeutic effects or toxicity.

The importance of metabolism lies in its role in determining the duration and intensity of a drug's effects. The metabolic processes can vary significantly between individuals, influenced by genetic factors, age, sex, pathology, and the presence of other medications, all of which can impact the efficacy and safety of pharmacotherapy. Understanding metabolism is essential for correctly dosing drugs and predicting potential interactions and side effects.