Biopharmaceutics & Drug Delivery Systems – Essential Study Notes for Easy Learning, Study notes of Biopharmaceutics and Pharmacokinetics

Download Biopharmaceutics & Drug Delivery Systems – Essential Study Notes for Easy Learning and more Study notes Biopharmaceutics and Pharmacokinetics in PDF only on Docsity!

BIOPHARMACEUTICS AND DRUG DELIVERY SYSTEM Biopharmaceutics: The study of the relation of the physical and chemical properties of a drug te its bioavailability, pharmacokinetics, and pharmacodynamic and toxicologic effects. - A drug product is the finished dosage form (eg, tablet, capsule, solution) that contains the active drug ingredient in association with nondrug (usually inactive) ingredients (excipients) that make up the vehicle or formulation matrix. Pharmacokinetics: The study of the time course of drug movement in the body during ADME (excretion and biotransfermation). Pharmacodynamics: The study of the relation of the drug concentration or amount at the site of action (receptor) and its pharmacologic response as a function of time. DRUG TRANSPORT AND ABSORPTION Drug abserption requires the drug +o be transported acress various cell membranes. Drug molecules may enter the bloodstream and be transported to the tissues and organs of the body. Drug molecules may cross additional membranes +o enter cells. Drug molecules may alse cross an intracellular membrane, such as the nuclear membrane or endoplasmic reticulum, to reach the site of action. General principles a. A cell membrane is a semipermeable structure composed primarily of lipids and proteins. b. Drugs may be transported by passive diff usion, partitioning, carrier-mediated transport, paracellular transpert, or vesicular transport. < Usually, proteins, drugs bound te proteins, and macromolecules de not easily cross cel] membranes. d. Nen polar lipid-soluble drugs traverse cell membranes more easily than de ionic or polar water- soluble drugs e. Low-mole-wt drugs diffuse across a cel] membrane more easily than do high mole-wt drugs.