Clinical Pharmacokinetics 2

Question 1

Maintenance doses

Answer 1

To maintain the plasma concentration within a specified range over long periods of therapy

At SS, dosing rate = elimination rate = CL*C/F

If intermittent doses: maintenance dose = dosing rate * dosing interval

Question 2

Loading dose

Answer 2

Achieve a target plasma level rapidly

Question 3

The dosing plan is base on

Answer 3

Therapeutic window
CL
Vd

Question 4

Continuous IV infusion

Answer 4

Rate of elimination = CL * C

Css = infusion rate/CL

Loading dose = Vd*TC/F

Question 5

Single IV injection

Answer 5

C will peak and decreae exponentially

Question 6

Multiple IV injection

Answer 6

C increases until SS is achieved
C fluctuates about a mean

Given smaller doses at a shorter intervals reduces the amplitude of the swings in C

Css and the rate at which SS is approached are not affected by dosing frequency

Question 7

Orally administered drugs

Single

Answer 7

Yields a more round peak

Changing the rate of absorption: rapid release vs. slow release

Slow release: delayed & lower peak, higher levels at later time > less frequent administration of drugs with short half-lives, prolong effects

Question 8

Orally administered drugs

Multiple

Answer 8

The oscillations in C are influenced by both rate of absorption and rate of elimination