Pharmacokinetics Overview

<p>The fraction of drug reaching systemic circulation (D)</p> Signup and view all the answers

<p>Volume of Distribution (Vd) (D)</p> Signup and view all the answers

<p>The time taken to reach the maximum plasma concentration (A)</p> Signup and view all the answers

<p>Cmax indicates the highest concentration of a drug in the plasma after administration (D)</p> Signup and view all the answers

<p>AUC (A)</p> Signup and view all the answers

<p>The fraction of drug removed by the liver during a single pass through the hepatic circulation. (A)</p> Signup and view all the answers

<p>ClH = ER * Q (B)</p> Signup and view all the answers

<p>Size, concentration, polarity, degree of ionization, and surface area of absorption site. (A)</p> Signup and view all the answers

<p>Diazepam (C)</p> Signup and view all the answers

<p>0.25 (B)</p> Signup and view all the answers

<p>Because they are rapidly metabolized by the liver, reducing their bioavailability. (A)</p> Signup and view all the answers

<p>Paracellular absorption occurs through tight junctions between cells, whereas transcellular absorption occurs through the cells themselves. (B)</p> Signup and view all the answers

<p>Metformin (D)</p> Signup and view all the answers

<p>Active transport can move drugs against their concentration gradient. (A)</p> Signup and view all the answers

<p>P-gp actively pumps drugs back into the intestinal lumen. (B)</p> Signup and view all the answers

<p>Decreased bioavailability due to reduced drug absorption (A)</p> Signup and view all the answers

<p>Rifampin (C)</p> Signup and view all the answers

<p>Increased plasma concentrations due to reduced drug elimination (B)</p> Signup and view all the answers

<p>Cyclosporine (C)</p> Signup and view all the answers

<p>Grapefruit juice inhibits intestinal CYP3A4 and OATP transporters. (A)</p> Signup and view all the answers

<p>Felodipine (B)</p> Signup and view all the answers

<p>Dairy products form insoluble complexes with certain drugs, reducing absorption. (B)</p> Signup and view all the answers

<p>BCS Class II (Low solubility, High permeability) (B)</p> Signup and view all the answers

<p>Enhancing solubility to accelerate dissolution. (A)</p> Signup and view all the answers

<p>A significant portion of the administered dose is absorbed into the systemic circulation. (C)</p> Signup and view all the answers

<p>Caco-2 cell permeability study. (D)</p> Signup and view all the answers

<p>Metoprolol and Propranolol. (D)</p> Signup and view all the answers

<p>1.2 - 6.8 (B)</p> Signup and view all the answers

<p>100% (B)</p> Signup and view all the answers

<p>They are designed to release the active drug over an extended period, affecting dissolution and absorption. (A)</p> Signup and view all the answers

<p>Follows Fick's Law of diffusion (C)</p> Signup and view all the answers

<p>Lipophilicity of the drug molecule (D)</p> Signup and view all the answers

<p>Transport of glucose into a cell using a protein transporter (B)</p> Signup and view all the answers

<p>Lipophilicity (D)</p> Signup and view all the answers

<p>The rate of transport reaches a maximum and cannot increase further (A)</p> Signup and view all the answers

<p>Movement across the cell membrane (D)</p> Signup and view all the answers

<p>These tissues have a highly selective barrier like the blood-brain barrier (B)</p> Signup and view all the answers

<p>L-Dopa (D)</p> Signup and view all the answers

<p>Enzymatic degradation of the drug in the stomach (B)</p> Signup and view all the answers

<p>To actively pump drugs back out of cells, reducing their absorption into the bloodstream (C)</p> Signup and view all the answers

<p>Kidney (D)</p> Signup and view all the answers

<p>To inactivate the drug and prevent it from causing side effects (D)</p> Signup and view all the answers

<p>Intravenous (D)</p> Signup and view all the answers

<p>Drugs are absorbed directly into the bloodstream from the mouth, bypassing the digestive system. (C)</p> Signup and view all the answers

<p>Rapid excretion from the body by the kidneys (C)</p> Signup and view all the answers

<p>Topical (B), Rectal (C), Intravenous (E), Sublingual/Buccal (F)</p> Signup and view all the answers

Signup and view all the answers

Transfer of a drug from site of administration into bloodstream.

Fraction of a drug reaching systemic circulation after administration.

Transport of a drug from bloodstream to tissues and organs.

Describes the apparent distribution of a drug in the body.

Chemical alteration of a drug, mainly in the liver.

Oxidation, reduction, hydrolysis reactions involving CYP450 enzymes.

Maximum plasma concentration of a drug after administration.

Time required to reach Cmax, indicating absorption rate.

A protein that moves substances across cell membranes, often against a concentration gradient.

Process used by cells to engulf large molecules, like Vitamin B12, into itself.

Drug passage through tight junctions between cells, affected by junction size and drug size.

Drug passage through the cell itself, dependent on drug lipophilicity and permeability.

Elements that govern how drugs move across membranes, including concentration gradient and size.

Describes the rate of diffusion of a drug across a membrane based on its properties.

Characteristic of active transport, where limited transporters mean a maximum rate.

A measure of a drug's ability to dissolve in fats, crucial for membrane permeability.

The process where a drug's concentration is significantly reduced before it enters systemic circulation.

The fraction of drug removed by the liver, calculated as (CA - Cv) / CA.

Volume of plasma cleared of drug by the liver per unit time, determined by blood flow and ER.

The proportion of a drug that enters systemic circulation after administration.

Drugs with an extraction ratio higher than 0.8, indicating lower oral bioavailability.

Drugs with an extraction ratio below 0.2, indicating high oral bioavailability.

The process where drugs diffuse across membranes without energy, from high to low concentration.

Carrier-mediated drug movement that requires energy (ATP) for absorption.

A transport protein that limits drug absorption by pumping drugs back into the intestine.

Increased P-gp expression leading to decreased drug absorption and lower bioavailability.

Decreased P-gp activity resulting in increased drug absorption and higher plasma concentrations.

A P-gp inducer that reduces the absorption of digoxin.

A P-gp inhibitor that increases the absorption of paclitaxel.

Inhibits CYP3A4 and OATP transporters, affecting drug absorption.

Grapefruit juice increases plasma concentration, risking hypotension.

Calcium in dairy can chelate with drugs, reducing their absorption.

Variation in gastric acid can affect drug stability, such as penicillin G.

Some drugs, like certain peptides, struggle to cross cell membranes.

P-glycoprotein and other transporters can reduce drug absorption.

Drugs can be inactivated by stomach pH or enzymes, example: omeprazole.

Methods to bypass poor oral bioavailability include IV, sublingual, and patches.

Loss of drug before reaching systemic circulation, occurring in GI, liver, lungs, and plasma.

Reduction of drug bioavailability during its first pass through the liver post-absorption.

≥ 85% of the dose is absorbed in humans.

≥ 85% of a drug dissolves within 30 minutes in standard media.

Drugs with a small range between effective and toxic doses, e.g., Warfarin.

Low solubility and high permeability; absorption limited by dissolution.

Highest dose dissolves completely in ≤ 250 mL of aqueous media at pH 1.2 - 6.8.

≥ 85% of the administered dose must be absorbed; involves extensive metabolism.

Includes human mass balance studies and Caco-2 cell permeability studies.

Drugs like Metoprolol, Propranolol, and Atenolol that dissolve easily.