ADME Flashcards
What is Fick’s equation?
It’s the rate of passive diffusion
Flux = DAK/X x (Concentartion gradient)
What are the forms of weak bases and weak acids that get trapped?
BH+ and A-
What is the hendersen hasselbach equation?
pH - pKa = log[nonprot]/[protinated]
What are two main carrier mediated transport systems??
ABC and SLC
Function of ABC
ATP-binding cassette (ABC) superfamily - Active transporters (1° mechanism) - Move substances out of cells or into cell organelles - e.g., p-Glycoprotein (MDR1)
Function of SLC
Solute carrier (SLC) superfamily - Participate in facilitated diffusion and active (2º) transport - Move substances into and out of cells - e.g., SERT, DAT (major role in the nervous system)
How do ABC and SLC work together?
- Pharmacologically important
- Work in concert to move compounds into and out of cells
Work with metabolizing enzymes to facilitate drug elimination
Targeted by specific drug therapies - Can account for many drug toxicities, drug-drug interactions, and inherited susceptibilities
What are some advantages and disadvantages of oral therapy administration?
Advantages: Easy administration, cost, safety, good patient adherence
Disadvantages: Destroyed by GI, 1st pass mech, variable rate
The equation for bioavalability is: AUC(oral)/AUC(iv)
T/F
T, a high f means good bioavalability
What are the three main pieces that regulate the ability for a drug to be effective and reach its destination?
● Relative tissue perfusion rates
● Plasma protein binding
● Partitioning between plasma and tissues
Where are perfusion rates high?
Kidney, brain, liver, lung. Not so in bone and fat.
Bound drugs do not cross membranes and pharm. inert (but may act as a reservoir). (T/F)
T, albumin binds many WAs and AGP binds many WBs
Storage, excretion (as a parent molecule), and biotransformation are all mechanisms of…
Termination of Drug Action
