Pharmacokinetics

Question 1

Pharmacokinetics

Answer 1

How he body affects the absorption of a drug and how that drug moves through the body.

Question 2

5 stages of pharmacokinetics

Answer 2

Liberation
Absorption
Distribution
Metabolism
Excretion

Question 3

Liberation

Answer 3

The release of the drug from its dosage form

Question 4

Absorption

Answer 4

The movement of drug from the site of administration to the blood circulation

Question 5

Distribution

Answer 5

The process by which drug diffuses or is transferred from intravascular space to extravascular space

Question 6

Metabolism

Answer 6

The chemical conversion or transfomation of drugs into compounds which are easier to eliminate

Question 7

Excretion

Answer 7

The elimination of unchanged drug or metabolite from the body via renal, biliary, or pulmonary processes.

Question 8

Types of liberation

Answer 8

Immediate: medicine is formulated to release the medicinal drug without delay

Delayed: the medicine is formulated to release medicinal drug sometime after it is taken

Extended: the medicine is formulated to make the drug available over an extended period allowing a reduction in dosing frequency.

Question 9

Routes of administration

Answer 9

Enteral
Parenteral
Mucous membranes
Topical/transdermal

Question 10

First pass metabolism

Answer 10

Term used for the hepatic metabolism of a pharmacological agent when it is absorbed from the gut and delivered to the liver via the portal circulation

Question 11

Bioavailability

Answer 11

Quantity of drug reaching systemic circulation/ quantity of drug administered

Question 12

Enteral routes

Answer 12

Oral

Rectal

Question 13

Parenteral routes

Answer 13

IV
IT
IM
SQ

Question 14

Factors affecting drug absorption

Answer 14

Administration route
Rate of dissolution of tablet
Drug formulation
Physical factors
Diffusion
Transport

Question 15

FIcks law

Answer 15

Fick’s law describes passive movement of molecules down its concentration gradient

Question 16

If pH < pKa

Answer 16

Protonated form dominates

Weak acids exposed to low pH diffuse across cell membranes, but weak bases do not

Question 17

If pH > pKa

Answer 17

Ionized form dominates

Question 18

pH trapping

Answer 18

Weak acid in a highly acidic environment –> largely protonated

In blood, a majority now exists in ionized form and cannot diffuse back to GI, trapping it in the blood

Question 19

Vd values

Answer 19

Vd < 0.071 L/Kg indicate the drug is mainly in the ciruclatory system

Vd > 0.071 L/Kg indicates the drug is most likely well distributed