Lecture 2 part 1

Question 1

Why Use PK tools?
Pk models offer ____________of complex body processes, providing a framework to predict a drug’s behavior within the body

Answer 1

simplifcations

Question 2

Quantitative Representation

A PK model acts as a hypothesis, utilizing mathematical expressions to concisely describe and establish quantitative relationships between various factors affecting drug kinetics

Question 3

Why use compartmental models?

Simplification: Compartmental models apply mathematical principles to various physiological processes, creating a ____________ representation.

Answer 3

simplified

Question 4

Why use compartmental models?

____________ Capability: The effectiveness of a model in predicting drug behavior is rooted in the accurate choice of mathematical functions that capture the key factors driving the kinetic process.

Answer 4

predictive

Question 5

Types of Models:
The basic types of compartmental models are
differentiated by the number of compartments
required to depict a drug’s behavior accurately.

Question 6

What is a Compartment?
It’s NOT an actual physiological or anatomical region. Instead, it represents a tissue or group of tissues with comparable blood flow and drug affinity.

Question 7

Notion of ‘Compartment’:
* Think of a compartment as a “kinetic space,” a
conceptual tool rather than a physical location.

Question 8

_________ Perfused Organs: Organs like the heart, liver, kidneys, and lungs are grouped into one compartment due to their analogous drug distribution patterns.

Answer 8

Highly

Question 9

_________Compartment: This compartment consists of plasma and highly blood-perfused organs. These organs and tissues rapidly equilibrate with the drug, making them central to its distribution.

Answer 9

central

Question 10

_____________ Compartment: This compartment includes fat tissue, muscle, cerebrospinal fluid (CSF), and other less perfused areas.

Answer 10

peripheral

Question 11

Determining Model Type: Observed drug concentrations in the body guide the selection of the appropriate compartmental model to accurately describe the drug’s pharmacokinetics.

Question 12

Compartmental Pharmacokinetics Models:

The value of a model is determined by:

How well it predicts _____________in fluids and tissues

Answer 12

drug concentrations

Question 13

Generally it is best to use the simplest model that accurately predicts changes in organ

Question 14

Pharmacokinetics Models

_____________ predictions: Foresee drug concentrations in plasma, tissues, and urine for any given dose or administration route.

____________Estimates: Predict potential accumulation of drugs and their metabolites

Concentration and Activity Correlation
Relate drug concentrations to their pharmacological
effects.

Impact of Physiological Changes
Understand how alterations in physiology or the
presence of disease influence drug absorption,
distribution, or elimination.

Answer 14

drug level

accumulation

Question 15

In first-order kinetics, the elimination rate or change in drug concentration is directly proportional to the amount of ________ present in the body

Answer 15

drug

Question 16

Mathematical Representation:

Rate = k * [Drug Concentration]

Where “k” is the first-order rate constant

Question 17

When plotted on a semilogarithmic graph, first-order kinetics produce a straight line, highlighting its constant proportionality.

Question 18

A majority of drugs in therapeutic settings follow first-order kinetics, making it easier to predict plasma drug
concentrations over time and adjust dosing regimens
accordingly

Question 19

Vd quantifies the distribution of a drug throughout the body.

It represents the volume wherein the drug appears to be dispersed.

Question 20

Conc = Mass / Volume

Question 21

𝐕𝐨𝐥𝐮𝐦𝐞 𝐨𝐟 𝐃𝐢𝐬𝐭𝐫𝐢𝐛𝐮𝐭𝐢𝐨𝐧=𝐀𝐦𝐨𝐮𝐧𝐭 𝐨𝐟 𝐃𝐫𝐮𝐠 𝐢𝐧 𝐭𝐡𝐞 𝐁𝐨𝐝𝐲/𝐏𝐥𝐚𝐬𝐦𝐚 𝐃𝐫𝐮𝐠 𝐂𝐨𝐧𝐜𝐞𝐧𝐭𝐫𝐚𝐭𝐢𝐨n