Chapter 3
Pharmacokinetics
Pharmacokinetics is a scientific discipline that focuses on the journey of a drug within the body, encompassing four key stages: absorption,…
Passive transport is a method of drug absorption where small, lipid-soluble drugs can move across the cell membrane. This movement happens along the…
Certain large, lipid-insoluble drug molecules that resemble amino acids, peptides, or glucose, require specialized carrier proteins to facilitate…
The process of oral drug absorption can be influenced by several factors. Weakly acidic drugs tend to be absorbed more readily from the stomach due…
Bioavailability refers to the proportion of an unaltered drug that, after administration, enters the systemic circulation and can be distributed to…
When a drug is taken orally, it undergoes a journey starting from the gastrointestinal (GI) tract, passing through the portal vein, reaching the…
Pharmaceutical equivalents, by definition, are drug products with the same active ingredient in the same quantities, encapsulated in identical dosage…
Presystemic elimination, or the first-pass effect, is the metabolism of drugs that reduces their effective concentration at the site of action. Apart…
The progression of a drug's impact can be analyzed by examining both the concentration-time course and the effect-time course. The…
Upon entering the systemic circulation, drugs can distribute into the interstitial and intracellular fluid of various tissue cells. This distribution…
Physiological barriers are semi-permeable cellular structures restricting drug diffusion into intracellular compartments and tissues. There are six…
Drugs predominantly attach to plasma proteins, with only a small percentage remaining unbound. The unbound portion can be calculated as one minus the…
The single-compartment model serves as a simplified representation of the human body. This model assumes that the body functions as a single,…
The two-compartment model divides the body into central and peripheral compartments to account for varying blood perfusion rates among organs and…
The volume of distribution refers to the theoretical volume necessary to contain the entire amount of an administered drug at the same concentration…
Pharmaceutical substances known as xenobiotics are predominantly lipophilic and nonionized. This enables them to permeate lipid bilayers, such as…
A phase I reaction is a biochemical process that introduces a functionally reactive polar group to a substance. This transformation predominantly…
Phase II reactions are essential for the detoxification and elimination of drugs from the body. These reactions involve the conjugation of parent…
The kidney serves as the primary organ responsible for eliminating drugs and their metabolites from the body. This process, known as renal…
During the process of renal excretion, as the glomerular filtrate progresses to the distal convoluted tubule (DCT), drugs that are highly permeable,…
Once the process of glomerular filtration is completed, blood carrying unfiltered drug molecules traverses through efferent arterioles and makes its…
Drug elimination refers to removing drugs from the body, either through urine by the kidneys or through bile by the liver. Drug clearance is a…
The liver plays a pivotal role in eliminating drugs and their metabolites, primarily through a process known as biliary excretion. This process…
Eliminating drugs from the body is a vital process that occurs through excretion or metabolism. Understanding the kinetics of drug elimination is…
A steady state refers to the level of a drug in the body once it has reached an equilibrium between administration and elimination. It represents the…
A drug dosage regimen describes the specific instructions and schedule for administering a drug to a patient. It considers factors such as drug…
A rational dosage regimen considers a drug's pharmacokinetics, including its absorption, distribution, metabolism, and elimination from the body.…
Fixed-dose regimens are a common approach to administer drugs to achieve and maintain desired levels of the drug in the body. In this dosing…
Prodrugs are a class of pharmaceutical compounds that undergo a biotransformation process within the body to be converted into a pharmacologically…
Sub-micrometer carriers (nanocarriers; NCs) enhance efficacy of drugs by improving solubility, stability, circulation time, targeting, and release.…
The recently introduced microphysiological systems (MPS) cultivating human organoids are expected to perform better than animals in the preclinical…
Knowledge of Fe bioavailability is critical to the assessment of the nutritional quality of Fe in foods. In vivo measurement of Fe bioavailability is…
