Unit 1- Pharmacokinetics

Question 1

Clearance

Answer 1

Volume of plasma containing total amount of drug removed in unit time mL/min or L/h

Question 2

Use of clearance

Answer 2

To assess excretory capacity of an organ

Question 3

Renal Clearance

Answer 3

Volume of plasma containing the amount of drug that is removed by the kidneys in unit time

Question 4

Total Body Clearance

Answer 4

Sum of clearance rates for each mechanism involved in eliminating the drug

Question 5

Rate of Drug Elimination

Answer 5

Amount of drug being eliminated per unit time, clearance is the proportionality factor to determine rate of elimination

Question 6

Overall Clearance Estimation

Answer 6

Estimated by measuring plasma concentrations at intervals following a single IV bolus

Question 7

Constant-Rate IV infusion

Answer 7

Used to determine drug clearance by measuring the plasma concentration at intervals, helps to calculate dose rate needed to achieve steady-state plasma concentration

Question 8

Constant IV Time curve

Answer 8

Plasma concentration increases from 0 but reaches a steady state plateau, and then drops off when infusion stops

Question 9

IV bolus Time Curve

Answer 9

Plasma concentration rises abruptly and then drops to 0

Question 10

Elimination Half-Life

Answer 10

Time necessary for plasma concentration to drop by 50%

Question 11

Increase in Distribution and half life

Answer 11

Increase in volume of distribution leads to more drug being sequestered in the tissues, and half life will increase

Question 12

Organs that sequester drugs

Answer 12

Fat and bones

Question 13

Increasing half life

Answer 13

Decreased renal or hepatic blood flow, decreased renal function, decreased metabolism

Question 14

Decreasing half life

Answer 14

Increased hepatic blood flow, decreased protein binding, increased metabolism

Question 15

First Order Elimination

Answer 15

Same volume of drug will be cleared by an organ regardless of plasma drug concentration, half life remains constant

Question 16

Zero Order Elimination

Answer 16

Occurs when mechanisms for first order elimination become saturated, rate of elimination is constant regardless of plasma drug concentration, half life varies

Question 17

Importance of Pharmacokinetics

Answer 17

interpret drug concentration, adjust dose regimens, identify drug interactions, individualize dose regimen

Question 18

Therapeutic Drug Montoring

Answer 18

To achieve desired therapeutic effect while minimizing adverse affects in each individual patient

Question 19

Pharmacokinetic Modeling

Answer 19

Used to predict behavior of a drug in the body, drug is given in a single dose, samples are collected over time

Question 20

Single Compartment Model

Answer 20

Body is considered one compartment, drug moves out of the body at a single rate

Question 21

Use of One Compartment Model

Answer 21

When plasma concentration falls exponentially after administration

Question 22

Two Compartment Model

Answer 22

Two compartments for the tissue and plasma, drug molecules can leave and enter the peripheral compartment via the central compartment by distribution constant and redistribution constant

Question 23

Multicompartment Model

Answer 23

Employed when experiments are conducted over long time frames, ie describing tissue residue of a drug in a food producing animal