Calculations

Question 1

How is fractional occupancy (P) calculated?

Answer 1

[D]/[D] + K_D

Question 2

How is concentration ratio calulated?

Answer 2

1+ ([Antagonist]/K_{<span>B</span>}(dissociation constant of antagonist)

Question 3

How is K_i calculated?

Answer 3

IC₅₀/1+ ([L]/K_D)

Question 4

What is the equation for the pH of a weak base?

Answer 4

pKa + log₁₀ ([B]/[BH+])

Question 5

What is the equation for the pH of a weak acid?

Answer 5

pKa + log₁₀([A-]/[HA])

Question 6

How is apparent volume of distribution (Vd) calculated?

Answer 6

amount of drug in body/concentration in plasma

Question 7

How is half life of a drug calculated?

Answer 7

(0.693 x V_d)/Cl

Question 8

How is rate of infusion of a drug calculated?

Answer 8

C_ss x clearance

Question 9

How is CssAv calculated?

Answer 9

(individual dose x oral bioavaliability)/(Interval between doses x clearance)

Question 10

How is the therapeutic index calculated?

Answer 10

LD₅₀/ED₅₀

Question 11

How is the therapeutic ratio calculated?

Answer 11

MTD/MED