equations to know

Question 1

volume of distribution

Answer 1

Vd = dose given / conc. of drug in plasma

Question 2

Vd < 3L means …

Answer 2

drugs retained in vascular compartments- remain in plasma

Question 3

Vd > 16L means …

Answer 3

drugs remain in both plasma and interstitial fluid

Question 4

Vd > 46L means …

Answer 4

drugs retained innon-vascular compartments– adipose, muscle etc.

Question 5

bioavailability

Answer 5

F % = drug in systemic circulation / drug administered

Question 6

bioavailability in IV meds

Answer 6

100%

Question 7

why is bioavailability decreased in oral meds

Answer 7

first pass metabolism

Question 8

elimination half life

Answer 8

t1/2 = 0.693 x Vd / CL

Question 9

how many half-lives to reach steady state?

Answer 9

5

Question 10

steady state (SS)

Answer 10

when rate of drug administered = rate of drug eliminated

Question 11

[drug]plasma

Answer 11

[drug]plasma = dosage rate / CL

Question 12

mean arterial blood pressure

Answer 12

MAP = (2x diastolic) + systolic / 3
MAP = CO x SVR

Question 13

cardiac output

Answer 13

CO = HR x SV

Question 14

membrane potential

Answer 14

Q = C x A x P

Question 15

what is Emax

Answer 15

maximum drug response

Question 16

what is EC50

Answer 16

conc. of drug required to produce half of Emax