Exam 1; Pharmacokinetics Flashcards
This is the study of the effect of the body on a given drug
pharmacokinetics
Pharmacokinetics is the basis for determining the amount of a drug when
which remains in the body at any given time after administration
What does Pharmacokinetics allow us to determine
the proper dose and dosage interval to achieve a desired therapeutic drug concentration
What is the only measurement of drug concentration that can easily be made in humans
the concentration of a drug in the plasma after administration; assuming the effect of the drug is proportional to its concentration in the blood
What is the α phase
the movement from blood to other tissues; redistribution
ignore this phase in pharmacokinetics
What type of graph is the log of serum concentration over hours
biphasic distribution curve
What is meant by the “first-order kinetics” of the drug concentration
a constant fraction of the drug is removed per unit of time
What is meant by the “zero-order kinetics” of the drug concentration
a constant amount of drug is removed per unit of time, regardless of the concentration of the drug (for example; ethanol)
What is the β phase used to calculate
the half life of the drug
What is the half life of a drug
the amount of time it takes for the concentration in plasma to decrease by half
The rate of elimination of a drug is proportional to what
the elimination constant times the amount of drug left
This is the fraction of drug removed per unit of time
elimination constant (Ke)
What is the fundamental pharmacokinetic equation
0.693 = Ke (T½)
This is a value which enables us to predict how much drug must be given to obtain a specific plasma concentration of a drug
apparent volume of distribution (Vd)
If the drug is taken up by cells, then the initial plasma concentration will be low, what does this say about the apparent volume of distributuon
it will be very high
