Module 3 Flashcards
Drugs _________ into compartments in the body where they may be _______, _________, ________ or exert their ___________ effect.
distribute stored metabolized excreted pharmacological
The extracellular fluid that surrounds cells. Low molecular weight, water soluble drugs distribute here.
Interstitial space
Includes the fluid in the interstitial space, intracellular fluid and the plasma
Total body water
The acellular component of blood.
plasma
Lipid soluble drugs tend to distribute here. The body’s fat stores.
Adipose tissue
Drug distribution is determined by three factors, what are they?
Blood flow to tissues
Ability of drug to move out of capillaries
Ability of drug to move into cells
The more drug that distributes out of the blood, the ______ the concentration of drug in the blood.
lower
What are well perfused organs/tissues (i.e. name them)?
Liver, kidney, brain
What are poorly perfused tissues/organs?
Fat, (muscle), bone, skin
Describe blood flow in newborns
Neonates have limited blood flow
Describe how heart failure or shock affects blood flow.
Decreased CO or BP reduces blood flow and can limit distribution
Describe blood flow in solid tumours.
The outer portion of solid tumours are well perfused; the innner region is not - hard to attain high drug concentrations within the tumour
Describe blood flow in abscesses.
They have no blood supply and are thus hard to treat with antibiotics. Often drained before drug therapy.
Drugs move out of capillaries through ________ except in the _______.
fenestrations
brain
What are the different ways in which drugs can pass the cell membrane?
Lipophilic - pass membrane
Transporter - hydrophilc drug
- efflux - pumps out
- uptake - pumps in
Most widely studied efflux transporter.
P-glycoprotein