Pharmokinetics

Question 1

What is pharmokinetics?

Answer 1

How the BODY effects the DRUG

Question 2

What are the four proccesses of pharmokinetics?

Answer 2

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

Question 3

Define Absorbtion

Answer 3

The movement of a drug from its site of administartion into the blood

Question 3

What do the four processes of pharacokinetics determine?

Answer 3

Concentration of a drug at the site of action( (via plasma drug levels)

Question 4

Do IV meds go through the process of absorption?

Answer 4

no, because they get injected directly into bloodstream

Question 5

What do rate and amount refer to when talking about absorption?

Answer 5

Rate: how SOON effects will be
Amount: how INTENSE effects will be

Question 5

Factors involving the body that affect absorbtion:

Answer 5

-route of administarion
-gastric emptying time for PO meds only
-surface area for absorption
-blood flow

Question 6

IV route PROS and CONS

Answer 6

Pros:
Absorbs into bloodstream, precise control, uses large fluid volume, can use drops

Cons:
-expensive fluid overload, risk of infection, and risk of embolism

Question 6

PO route PROS and CONS

Answer 6

PROS:
-most convient, preffered route, can be reversed with charcoal

CONS:
-highly variable absorption, can’t control concentration, first pass effect, GI upset

Question 7

Factors involving the drug that affect absorbtion

Answer 7

-Solubulity, dissolution rate, chemical structure. ionization

Question 8

IM and SC injection PROS and CONS

Answer 8

PROS:
absorbs into capillary wall, used for poorly soluble drugs

CONS:
discomfort, nerve damage, risk of infection

Question 9

What are the 3 types of PO meds? describe them

Answer 9

1. Tablet: dissolves in stomach
   2.Enteric coated: dissolves In small intestine
2. Sustained release: capsules with spehers (think tylenol costco)

Question 10

Golden rule of solubility

Answer 10

Like dissolves like.
Lipid soluble things can pass membrane because membrane is fatty

Question 10

What is solubility all about?

Answer 10

Crossing the phospholipid cell membrane

Question 11

Can lipid soluble things pass cell membrane?

Answer 11

yes!

Question 12

Can large molecules pass cell membrane?

Answer 12

No, they won;t go through at all

Question 13

can polar/water soluble things pass?

Answer 13

maybe. but its very hard

Question 14

Can charged molecules make it across cell membrane?

Answer 14

nope.

Question 15

what is P-glycoprotein (PGP)?

Answer 15

an active transport system in our cells that transports drugs OUT of cells

Question 16

what two areas in the body are PGP levels high?

Answer 16

-the brain and the placenta

Question 17

What happens when an acidic drug enters a basic enviorment?

Answer 17

it donates a proton and it ionizes, menaing it won’t absorb or corss cell membrane

Question 18

what happens when a basic drug enters an acidic enviorment?

Answer 18

it takes a proton and ionizes. Not it won’t cross membrane

Question 19

The stomach is a ______ enviorment.

Answer 19

acidic

Question 20

The Small intestine is a ______ enviorment

Answer 20

basic

Question 21

explain how the PH of a med effects it's ability to be absorbed with the example of aspirin which is an acidic med?

Answer 21

-aspirin is NON IONIZED in the stomach (since both are acidic) so it CAN be absorbed -Asprin in ionized in the Small Intestine, so it would NOT be absorbed and it would acumalate there.

Question 22

What is ion trapping?

Answer 22

if a med gets ionized, its trapped on that side of membrane it got ionized in