Pharmacology Fundamentals

The science of drugs, their origins, compositions, pharmacokinetic use, toxicology, etc.

A drug is a substance with a biochemical or physiological effect, whereas a medicine is a carefully produced, tested, approved, and regulated substance used to prevent, alleviate, or cure symptoms or disease.

Aspirin, derived from the willow tree, is used for its anti-inflammatory effects.

<p>Drugs can be named using their chemical name, generic name, or brand name.</p> Signup and view all the answers

<p>Scientists, clinicians, pharmaceutical companies, and regulators all play important roles in the drug development process.</p> Signup and view all the answers

<p>The therapeutic index is the blood concentration ratio at which a drug causes death or toxicity to the amount that causes a therapeutic effect.</p> Signup and view all the answers

<p>Paracetamol is an example of a drug with a narrow therapeutic index.</p> Signup and view all the answers

<p>Banting's discovery of insulin for the treatment of diabetes, and Alexander Fleming's discovery of penicillin in mould, were significant milestones in the development of pharmacology.</p> Signup and view all the answers

<p>Drug absorption is the process by which a drug moves from its site of administration to the systemic circulation. Hydrophilic drugs use the paracellular pathway to cross the cell membrane.</p> Signup and view all the answers

<p>The two approaches to estimate drug solubility are LogP and Polar Surface Area (TPSA).</p> Signup and view all the answers

<p>ABC transporters are efflux transporters that only move drugs back out into the systemic circulation, whereas SLC transporters are influx transporters.</p> Signup and view all the answers

<p>Caco-2 cells are used in vitro to predict the intestinal permeability and efflux liability of a drug. A drug is added to either the apical or basolateral side of the membrane, and its concentration is measured by taking samples from each side.</p> Signup and view all the answers

<p>The three in vitro approaches are: 1) Transporter knockout (KO) Caco-2 cell lines, 2) Cells transfected with the transporter of interest, and 3) Inhibitor of the transporter of interest.</p> Signup and view all the answers

<p>The major body compartments in drug distribution are: intravascular fluid, interstitial fluid, intracellular fluid, and body fat.</p> Signup and view all the answers

<p>Plasma protein binding decreases the free, unbound drug concentration, which reduces drug metabolism, distribution, and renal clearance.</p> Signup and view all the answers

<p>The two important plasma proteins for drug binding are alpha1 acid glycoprotein and human serum albumin (HSA).</p> Signup and view all the answers

<p>Lipophilic drugs can cross cell membranes and accumulate in body fat. In obese individuals, highly lipophilic drugs may accumulate in excess, leading to altered pharmacokinetics.</p> Signup and view all the answers

<p>Blood flow affects drug distribution by initially distributing drugs to well-perfused organs (heart, brain, liver, lungs) and then to poorly perfused tissues.</p> Signup and view all the answers

<p>To metabolize xenobiotics/drugs using NADPH and O2</p> Signup and view all the answers

<p>CYP3A4 has broad substrate specificity, while CYP2D6 is highly polymorphic</p> Signup and view all the answers

<p>Exaggerated drug effects or toxicity due to reduced hepatic metabolism</p> Signup and view all the answers

<p>It is used as a pharmacokinetic enhancer to reduce the metabolism of co-administered HIV drugs</p> Signup and view all the answers

<p>Drug excretion is the irreversible physical removal of a drug and its metabolites from the body, whereas drug elimination includes both metabolic and excretory processes</p> Signup and view all the answers

<p>Fu is the fraction of drug unbound in plasma, which is important for calculating drug excretion through glomerular filtration</p> Signup and view all the answers

<p>It involves transporters, such as SLC transporters, in the proximal tubular cells</p> Signup and view all the answers

<p>Urine pH affects drug ionization and reabsorption, with acidic pH increasing reabsorption of basic drugs</p> Signup and view all the answers

<p>They are used to investigate drug metabolism</p> Signup and view all the answers

<p>It can lead to increased metabolism of co-administered drugs, potentially reducing their effects</p> Signup and view all the answers

<p>No fenestrations on endothelial cells, tight junctions, and efflux transporters</p> Signup and view all the answers

<p>Brain and placenta; to regulate the movement of substances into and out of these organs</p> Signup and view all the answers

<p>Transporters facilitate drug uptake in the liver and brain penetration, while efflux transporters return drugs back into circulation</p> Signup and view all the answers

<p>Volume of distribution is the extent of drug movement from plasma into tissues; it affects plasma concentration and body compartment distribution</p> Signup and view all the answers

<p>Liver and gut wall; first-pass metabolism decreases the bioavailability of orally administered drugs</p> Signup and view all the answers

<p>Phase 1: oxidation, hydrolysis; phase 2: glucuronidation; examples: tenofovir, codeine, morphine</p> Signup and view all the answers

<p>Increase molecular size, decrease drug elimination half-life, alter pharmacological activity, and terminate drug action</p> Signup and view all the answers

<p>CYP450 are drug-metabolizing enzymes found on the ER of hepatocytes; they facilitate the biotransformation of drugs</p> Signup and view all the answers

<p>Efflux transporters return drugs back into circulation, limiting drug distribution into the brain</p> Signup and view all the answers

<p>Transporters facilitate the efflux of drugs back into circulation, limiting drug distribution into the brain</p> Signup and view all the answers

<p>Morphine undergoes hepatic metabolism, converting into conjugates that are excreted into bile and concentrated in the GI tract. Bacteria in the GI tract, such as B-glucuronidase, can hydrolyze these conjugates back into morphine, which is then reabsorbed into the systemic circulation, prolonging its effects.</p> Signup and view all the answers

<p>Intrinsic factors, such as age, genetics, sex, and disease status, and extrinsic factors, such as concomitant medication, diet, and exposure to chemicals and other environmental causes.</p> Signup and view all the answers

<p>CYP SNPs can influence the phenotype of metabolizers in the population, leading to variations in drug metabolism and response, and thus affecting the efficacy and toxicity of the drug.</p> Signup and view all the answers

<p>Fe is low for hepatically cleared drugs, as they undergo metabolism and the metabolites are excreted, whereas Fe is high for renally cleared drugs, as a majority of the parent drug is excreted unchanged in the urine.</p> Signup and view all the answers

<p>Administer a single dose of the drug, collect blood samples, and measure the drug plasma concentration-time curve at defined times to calculate the area under the curve (AUC).</p> Signup and view all the answers

<p>Drug bioavailability is the fraction of the administered dose that reaches systemic circulation. It is determined by calculating the AUC of the orally administered drug and comparing it to the AUC of the same dose administered intravenously.</p> Signup and view all the answers

<p>Drug clearance is the ratio of the elimination rate to the concentration of the drug in plasma.</p> Signup and view all the answers

<p>Hepatic metabolism converts the parent drug into conjugates that are excreted into bile and then reabsorbed, prolonging the effects of the drug.</p> Signup and view all the answers