1.1 : 生物药剂学和药代动力学：概述

Drugs come in various dosage forms, including solids, liquids, semisolids, or aerosols.

These formulations deliver drugs at the site of action, triggering the desired therapeutic effects and alleviating medical conditions. The effectiveness of these drug products relies on the drug's physicochemical properties, formulation, and administration route.

Biopharmaceutics explores how these factors impact a drug's systemic absorption, influencing its availability at the target site and therapeutic outcomes.

Now, drugs administered orally, intravenously, subcutaneously, intramuscularly, or intranasally undergo various pharmacokinetic processes– absorption, distribution, metabolism, and elimination.

Absorption involves the transfer of drugs into the bloodstream, facilitating their distribution to the body's tissues, ultimately reaching their target. The drug may then be biotransformed by metabolism and finally eliminated by the body, either in its original or metabolized form.

Understanding pharmacokinetic parameters helps design an optimal drug regimen, including choosing the route of administration, determining dosing frequency, and defining the treatment duration.