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Question 1

Pharmacokinetic definition:

Answer 1

MAthematical description of drug movement throughout the body

Question 2

ADME:

Answer 2

Absorption, Distribution, Metabolism, Elimination

Question 3

Pharmacodynamics definition:

Answer 3

How the drug interacts with the target

Question 4

Describe the drug concentration graph for an orally administered drug. IV adminstered drug.

Answer 4

The orally administered drug follows the normal curve of ADME.
IV injected drugs lack the absorption phase

Question 5

Define AUC and what it indicates:

Answer 5

Area under the plasma concentration curve. Indicates the rate and extent of drug absorption.
It is a total concentration of drug in systemic circulation as a function of time

Question 6

What drug is the AUC important for and why?

Answer 6

Fluroquinolones. Activity depends on AUC above MIC

Question 7

Define Tmax and Cmax and what they indication

Answer 7

Tmax: Time taken to reach maximum plasma drug concentration. This is a rate of absorption indicator
Cmax: this is the max concentration reached in plasm. Extent of drug absorption indicator

Question 8

Use Tmax and Cmax for IV, SQ, and IM injections True/False

Answer 8

FALSE; These are not applicable for IV injections

Question 9

What is the activity of Beta-lactam drugs dependent on?

Answer 9

Time drug concentration is above MIC

Question 10

What is the activity of aminoglycosides dependent on?

Answer 10

Cmax above MIC (Ideally more than 10x)

Question 11

Describe the one compartment model.

Answer 11

Absorption is at one time point as it is administered via IV. The drug does not distribute in the other tissues. The clearance rate is expressed as Kel. Elimination is done via the kidney, liver, GIT.

Question 12

Describe a zero order elimination:

Answer 12

This means that the drug is eliminated at a constant amount over a period of time.

Question 13

Describe a first order elimination:

Answer 13

The drug is eliminated at a constant % over a period of time.

Question 14

Define Clp

Answer 14

This is the amount of plasma cleared of a drug per unit time per unit bodyweight

Question 15

Why is clearance rate important?

Answer 15

Excretion of drugs are affected by kidney failure. If you have 2x plasma creatinine concentration = aminoglycoside toxicity

Question 16

Define T1/2

Answer 16

This is elimination half time. It is the time that it takes for the concentration in the plasma to decrease by half.

Question 17

What is half-life dependent on?

Answer 17

Speed of elimination process (Clp)

Exposure of drug to elimination

Question 18

Doubling the dose does what?

Answer 18

Doubles the Cmax

Adds a half-life

Question 19

Doubling the dose does not change what?

Answer 19

The half-life time

Tmax

Question 20

What’s the difference in treating gram negative and gram positive bacteria?

Answer 20

Gram negative bacteria have the outer envelope; more important to make sure right dosage of drug is in the body

Question 21

Describe a two compartment model:

Answer 21

This is when a drug can readily diffuse out of the central compartment. This is used to treat skin, eyes, prostate, etc. Biexponential IV curve has a bend in the curve.

Question 22

Where does elimination occur in the two compartment model?

Answer 22

Still the central compartment only.

Question 23

Describe the two phases in a two compartment model

Answer 23

Alpha phase: Fast; distribution of drug into peripheral tissues
Beta phase: Slow; elimination of drug from the central compartment

Question 24

Describe Flip-Flop Kinetics

Answer 24

This is when absorption occurs slower than elimination; see in three compartment models

Question 25

What portion of the three compartment model is of concern when it comes to residues?

Answer 25

Terminal gamma portion

Question 26

What is the volume of distribution?

Answer 26

This is the amount of drug in the body divided by the plasma drug concentration

Question 27

What is the clinical application of Vd?

Answer 27

The smaller the Vd, the less likely the drug is to distribute to other parts of the body

Question 28

How do you calculate half time?

Answer 28

Volume of distribution divided by clearance rate

Question 29

How is bioavailability calculated?

Answer 29

Compare the AUC of IM/SQ/Oral route against the AUC for IV administered drugs

Question 30

What is the bioavailability of an IV drug?

Answer 30

100%

Question 31

What drugs are usually highly protein bound?

Answer 31

Ionized drugs: NSAIDs, Penicillin, and Sulfonamides

Question 32

What three effects make a long acting drug long acting?

Answer 32

High protein binding
Slow absorption
High distribution volume