Pharmacokinetics 1 Flashcards
In ADME what is metabolism and excretion called as a whole?
Elimination
e.g. IV injection (ADME)
skips absorption step - automatically 100% of the drug will be directly injected (absorbed essentially)
when taking tablet orally what is the phases after consumptoion?
absorption phase (increase and hit peak = rate of elimination is greater than absorption)
rate will slow down and return to zero (elimination phase)
when taking tablet orally what is the phases after consumptoion?
absorption phase (increase and hit peak = rate of elimination is greater than absorption)
rate will slow down and return to zero (elimination phase)
PK: Pharmaceutics factors we will consider
Bioavailability (F)
Solubility – considered in detail in semester 1
Partitioning – process of molecules distributing (partitioning) themselves between two domains
pH-partition theory – brings together the Henderson-Hasselbalch equation and partitioning to explain absorption of drugs
Salt factor – considers the fact that the drug may be in the form of a salt or a prodrug, e.g. an ester
Bioavailibility (F) =
fraction of administered dose of drug which reaches system circulation (intact)
different dosage forms can have an impact on
pharmacokinetics
AUC
area under the curve
What are the Integral branches of Pharmacology?
Pharmacodynamics, PD
drug does to the body?
Drug action & Mechanisms
Pharmacokinetics, PK
body does to the drug?
Barriers (ADME)
“drug elicits specific physiological response”
1) biological
2) chemical
1) “right target”
2) “right target binding site”
Administration & Absorption
For drugs reaching target via blood/plasma (systemic circulation):
“the magnitude of drug effect is associated to [drug] available in the plasma/blood)”
Such kinetics may not be TRUE, if
the drug effect is mediated through a metabolite
the drug effect is irreversible
follow different kinetics in the target
compartment (different from blood)
