Pharmacokinetic Phase

Question 1

PHARMACOKINETIC PHASE
What are the 4 processes of drug movement to achieve drug action?

Answer 1

○ Absorption
○ Distribution
○ Metabolism / Biotransformation
○ Excretion

Question 2

ABSORPTION
Where does this happen?

Answer 2

Absorption happens in the small intestine bc of the action of
the mucosal villi.

Question 3

Movement of drug particles from GIT to body cells, by?

Answer 3

Passive and Active Absporption

Question 4

Passive Absorption

Answer 4

by principle of diffusion,
area of higher cont to the area of lesser cont.
Readily pumapasok yung cell

Question 5

Active Absorption

Answer 5

hindi agad agad pumapasok
yung gamot inside the cell. It needs a carrier
(enzyme or protein) so the drug in the blood can
pass through

Question 6

Pinocytosis

Answer 6

the cell will engulf the drug.

Question 7

Drugs that are lipid-soluble and non-ionized (not
charged) are?

Answer 7

Drugs that are lipid-soluble and non-ionized (not
charged) – are absorbed faster in the GIT than water-soluble
and ionized drugs

Question 8

Cell membranes are?

Answer 8

Cell membranes are lipid-soluble kaya kung
ganun din yung gamot, very easy siya
makakapasok ng cell by passive absorption

Question 9

If drug is water-soluble

Answer 9

If drug is water-soluble, mahirap siya
makapasok. It passes thru a carrier (active
absorption).

Question 10

Water-soluble and Ionized Drugs undergo what kind of absorption?

Answer 10

Active absorption

Question 11

First-pass Effect
give examples

Answer 11

First-pass Effect – is a process where some oral drug
passes to the liver first.
Examples are: Morphine and Warfarin

Question 12

HIGH first-pass

Answer 12

• When a drug has a very high first-pass, they are not recommended to have an oral form.
• Sometimes drugs with high first-pass have around 20-40% bioavailability lang. So when it reaches the systemic circulation, 20-40% nalang yung natira from the original dose.

Question 13

Examples of high first-pass drug

Answer 13

Lidocaine and some nitroglycerines.

Question 14

Bioavailability

Answer 14

Bioavailability – is the percentage of administered drug
dose that reaches systemic circulation

Question 15

Oral drugs’ bioavailability is?

Answer 15

Oral drugs’ bioavailability is ALWAYS LESS
than 100%, esp if it has a high first-pass.

Question 16

Drugs that have 100% bioavailability are drugs
that are given via?

Answer 16

IV ROUTE (derecho bloodstream).

Question 17

DISTRIBUTION

Answer 17

Process by which the drug becomes available to body fluids
and body tissues.

Question 18

Distribution is influenced by?

Answer 18

Protein-binding
Blood flow
Body tissue affinity

Question 19

Protein-binding percentages:
Highly protein bound
Moderately Highly protein bound
Moderately protein bound
Low protein bound

Answer 19

1. Highly protein bound > 89%
2. Moderately highly protein bound 61% - 89%
3. Moderately protein bound 30% - 60%
4. Low protein bound < 30%

Question 20

Why do he have to be cautious when giving highly protein bound drugs?

Answer 20

Be cautious when giving highly protein-bound
drugs because giving them together at the
same time can cause an increase in the
free/active drug in the bloodstream causing
overdose; The elderly and malnourished
people has less protein, meaning if given a
highly protein bound drug— there might be an
increase in a free drug

Question 21

Free drugs

Answer 21

are active drugs that are not bound to protein
and can cause a pharmacological response

Question 22

METABOLISM OR BIOTRANSFORMATION

Answer 22

The chemical activity of our body when we take a drug.

Question 23

Half-life of a Drug

Answer 23

s the time it takes for one half of the drug
concentration to be eliminated.

Question 24

steady state of serum concentration

Answer 24

dealing with the predictive, therapeutic effect of the drug

Question 25

Half-life of a Drug is affected by?

Answer 25

Metabolism and Elimination

Question 26

EXCRETION OR ELIMINATION: Routes of Drug Elimination?

Answer 26

○ Kidneys (Main Route for Elimination)
○ Liver Metabolism
○ Bile
○ Feces
○ Lungs
○ Saliva
○ Sweat
○ Breastmilk

Question 27

Summary of Pharmacokinetic phase

Answer 27

Drug administration:
1. Oral - Absorption - Distribution - Metabolism - Billary Excretion / Intestinal Excretion / Renal Excretion
2. IV - Distribution - Metabolism - Billary Excretion / Intestinal Excretion / Renal Excretion