Pharmacolocy

Question 1

Volume of distribution

Answer 1

= amount of drug in body / plasma drug concentration

• low = blood
• medium = ECF
• high = all tissues

Question 2

Drug Clearance

Answer 2

= rate of drug elimination / plasma drug concentration

= Vd x Ke (Ke is elimination constant)

Question 3

Half-life

Answer 3

= (0.693 x Vd) / (CL)

Question 4

Loading Dose

Answer 4

= (Cp x Vd) / F

Cp is target plasma concentration
(F is fractional bioavailability)

Question 5

Maintenance Dose

Answer 5

= (Cp x CL x tau) / F

Cp is target plasma concentration
(F is fractional bioavailability)(tau is dosage interval)

Question 6

Therapeutic Index

Answer 6

= TD50 / ED50

TD50 is toxic median dose
(ED50 is effective median dose)