non-compartmental analysis Flashcards
What PK properties can we quantitate?
Absorption
Distribution
Metabolism
Elimination
The rate of absorption describes how ________ a drug is absorbed. It is characterized by ________ and _______ in pharmacokinetics.
quick; first-order absorption rate constant (ka); the time it takes to reach the maximum plasma concentration (tmax)
The extent of absorption describes how _______ a drug is absorbed. It is characterized by _____ and _____ in pharmacokinetics.
much; bioavailability (F); AUC
For intravenous administration, the bioavailability value should be _______. For non-intravenous administration, the bioavailability value should be _______.
F=1; 0<F<1
T/F - Dose in the system can be interpreted as the amount of drug in the body except for the unabsorbed drug in the GI.
True
In pharmacokinetics, drug distribution is primarily characterized by _______, which represents _______ (distribution of drug in tissue/distribution of drug in plasma/relative distribution of drug between tissue and plasma).
volume of distribution; relative distribution of drug between tissue and plasma
Elimination consists of _______ and _______.
metabolism; excretion
Total clearance is a proportionality constant relating _______ to _______.
the rate of elimination; plasma drug concentration
T/F A drug is considered being eliminated only after it leaves the body
False - A drug is considered to be eliminated after it is metabolized and transformed to a different chemical species.
Disposition = ________ + ________
distribution + elimination
disposition = ________ + ________ + ________
distribution + metabolism + excretion
List 3 examples that when dose is changed, the PK variable will change proportionally under linear PK
concentration (C), AUC, elimination rate (dA/dt)
List 5 examples that when dose is changed, the PK variable will stay unchanged under linear PK
V, CL, ka, t1/2, k
List the 3 primary PK parameters
V - volume of distribution
CL - clearance
ka - absorption rate
List 3 secondary PK parameters
t1/2, Cmax, tmax, AUC, F
T/F If a drug has a large volume of distribution, its total clearance is likely to be low.
F - a drug having a large volume of distribution does not mean that the drug will have a low total clearance. The information is sufficient for us to make the interpretation.
T/F - If a drug has a low total clearance, there will be more drug in the tissue and thus the volume of distribution should be large.
F - If a drug has a low total clearance, there will be more drug in both of the tissue and plasma and thus the volume of distribution should be unchanged.
T/F - If the ka of a drug increases, its V and CL will increase
F - If the ka of a drug increases, its V and CL will be likely to stay the same
If a drug has a V value of 15 L, it will be likely to distribute in _________
blood/plasma, interstitial/extracellular fluid
If a drug has a V value of 25 L, it will be likely to reach ________
intracellular space
Regarding mass balance, dose = ________ + ________ + _________ + __________
amount at the absorption site; amount in body; amount metabolized; amount excreted
Regarding mass balance, rate of change of drug in body = _________ - _________
input rate; output rate
Regarding mass balance, rate of change of drug in body = _______ - (_______ + _______) = _________- __________ - _________
rate of absorption - (rate of excretion + rate of metabolism) = rate of absorption - rate of metabolism - rate of excretion
When ready state is reached, input rate ______ output rate
equals
