L5: Drug absorption

Question 1

• study of the mechanism of drug action on living tissue at the cellular
level. “What the drug does to the body”

Answer 1

• Pharmacodynamics:

Question 2

• the study of the concentration of a drug during the processes of absorption, distribution, biotransformation (metabolism), and excretion/elimination of a drug.

Answer 2

Pharmacokinetics

Question 3

The study of the biologic activity that a drug has on a living system.

Answer 3

Pharmaco-dynamics

Question 4

1. the mechanisms of action of the drug
2. the actions of the drug

Answer 4

Pharmaco-dynamics

Question 5

• Deals with the magnitude and time course of drug effect

Answer 5

Pharmaco-kinetics

Question 6

• Deals with the:
Absorption,
Distribution
Metabolism Excretion/elimination
• of drugs

Answer 6

Pharmaco-kinetics

Question 7

1. Absorption
2. Distribution
3. Metabolism
4. Excretion/ elimination

Answer 7

I. pharmacokinetics

Question 8

Is the transfer of a drug from its site of administration to the blood.

Answer 8

ABSORPTION

Question 9

IV delivery absorption is complete.

Answer 9

ABSORPTION

Question 10

Factors that affect absorption: absorption depend on

Answer 10

A. The environment where the drug is absorbed
1. Blood flow to the absorption site
2. Total surface area available for absorption
3. Effect of pH on drug absorption
B. Chemical characteristics of the drug
C. Therouteofadministration.

Question 11

Drug must cross biologic membrane barriers

Answer 11

I. Mechanisms of passage across membranes

Question 12

. To be absorbed,
2. To reach its site of action
3. To be eliminated.

Answer 12

I. Mechanisms of passage across membranes

Question 13

The characteristics of a drug that predict its movement Across membranes:

Answer 13

1. Its molecular size,
   • Small molecules (Water, glycerol) permeate readily • Large organic molecules diffuse more slowly.
2. Degree of ionization
3. Lipid solubility
4. Its binding to plasma proteins or tissue proteins.

Question 14

Passive diffusion: the most common

Answer 14

Mechanisms of absorption

Question 15

The drug moves from a region of high concentration to one of lower concentration.

Answer 15

Mechanisms of absorption

Question 16

is the process of spontaneous passive transport of molecules or ions across a biological membrane via specific transmembrane integral proteins.

Answer 16

b. Facilitated diffusion

Question 17

Involves a specific carrier protein
- Is “energy dependent” & is driven by the hydrolysis of ATP
- Also capable of moving a drug against a concentration gradient

Answer 17

C. Active Transport

Question 18

a substance is engulfed and internalized by the
cell.

Answer 18

d. Endocytosis

Question 19

It plays a minor role in the transport of most
drugs.

Answer 19

d. Endocytosis