ADME and Pharmacokinetics Flashcards
what is pharmacokinetics
how the body handles drugs- the process the drug is subject to once in the body
what is pharmacodynamics
what the drug does to the body
what processes are absorption
all processes from the site of administration to the site of measurement
what is bioavailability relating to absorption
measure of the extent of absorption of unchanged administered compound
what is distribution
reversible transfer of substance between site of measurement and other sites within the body
distribution is _______ transfer
reversible
define metabolism
irreversible loss of unchanged substance by chemical conversion- physiochemical properties of the drug are altered
what can elimination and excretion be clumped together as?
disposition
PK behaviour is a function of what 4 things?
Physicochemical and structural properties of drug
Dosage form
Route of drug administration
Physiology of the body
poor PK properties may limit what? can lead to?
clinical application- ending in drug termination
factors of a person that can influence the drugs PK
genetics, size, age, disease, co-administration of other drugs, environmental factors (smoking)
3 types of PK models for the ADME process?
- single equation: integrated or differential
- kinetic compartmental models
- physiologically based PK models
explain what single equation PK model is?
integrated or differential
shows decline of drug concentration time
which of the single equation PK models do we look at?
INTERGRATED
integrated equation?
C= C0e^-kt
what is the kinetic compartmental method used for?
to describe the data
number of compartments defined by the data
what type of data is kinetic compartmental models used for?
for fitting of sparse clinical data- population PK modelling
when are physiologically based PK models used?
at the end- give much more detail
what is physiologically based PK models used for?
predicting in vivo pharmacokinetics from in vitro data
off target effects of drugs are associated with?
minor toxicity or if too high then serious toxicity
can you modify the PK properties of molecules?
yes
what is the difference between physiologically based (PBPK) model and compartmental model?
has a mechanistic nature- equations can show exactly what happened
drug independent physiological parameters?
PBPK model
tissue volumes and blood flow
tissue composition
intestinal pH and transit time
enzyme and transporter abundance
population and external factors to consider with PBPK model?
age gender race disease status genetics smoking and diet
drug dependent factors for PBPK model
LogP, pKa, B/P, molecular weight permeability solubility particle size CLmax
what can PBPK models allow simulations of?
drug plasma and tissue concentration time profiles after iv and oral administration
