Steady state is reached after about 5 × 12 = 60 hours. Pharmacokinetics (from Ancient Greek pharmakon "drug" and kinetikos "moving, putting in motion"; see chemical kinetics ), sometimes abbreviated as PK, is a branch of pharmacology dedicated to describing how the body affects a specific substance after administration.
Last Update: July 30, 2023. Pharmacokinetics (PK) is the study of how the body interacts with administered substances for the entire duration of exposure (medications for the sake of this article). This is closely related to but distinctly different from pharmacodynamics, which examines the drug’s effect on the body more closely.
A thorough understanding of pharmacokinetics is essential in building treatment plans involving medications. Pharmacokinetics, as a field, attempts to summarize the movement of drugs throughout the body and the actions of the body on the drug.
Pharmacokinetics is based on mathematical modeling that places great emphasis on the relationship between drug plasma concentration and the time elapsed since the drug's administration. Pharmacokinetics is the study of how an organism affects the drug, whereas pharmacodynamics (PD) is the study of how the drug affects the organism.