Pharmacology
Pharmacokinetics (PK)
Definition
Pharmacokinetics is the branch of pharmacology concerned with how the body processes a substance over time, commonly described by the acronym ADME: Absorption (how and how fast the compound enters the bloodstream), Distribution (how it spreads through tissues), Metabolism (how it is biochemically modified), and Elimination (how it is removed from the body). For peptides, pharmacokinetic considerations are especially important because native peptides typically have very short half-lives due to rapid proteolytic degradation and renal clearance. Structural modifications such as PEGylation, fatty acid acylation, cyclization, and D-amino acid substitution are employed to improve the pharmacokinetic profiles of research peptides.