Which one is not a step of pharmacokinetics?

A) Distribution:. Distribution refers to the process by which a drug is transported throughout the body after it is absorbed into the bloodstream. It involves the movement of the drug to various tissues and organs, where it can exert its effects. Factors such as blood flow, tissue permeability, and protein binding affect distribution. B) Metabolism: Metabolism refers to the biochemical process by which the body breaks down drugs into metabolites, usually in the liver. Metabolism can transform drugs into more easily excreted forms and sometimes alters the drug’s activity. It is essential for drug clearance and can affect drug efficacy and toxicity. C) Absorption: Absorption is the first step in pharmacokinetics, where the drug enters the bloodstream after being administered. It occurs primarily in the gastrointestinal (GI) tract for oral medications but can also happen in other routes like subcutaneous or intramuscular injections. The rate and extent of absorption are influenced by factors such as drug formulation, route of administration, and presence of food. D) Synthesis: Synthesis refers to the process of creating substances, such as drugs or other compounds, typically within the body or in a laboratory setting. While drug synthesis is crucial in drug development, it is not a step involved in the movement or processing of drugs within the body (which is what pharmacokinetics describes). Pharmacokinetics focuses on how the body handles drugs, not how they are created.