Pharmacokinetics Flashcards
non-polar molecules have ____ bonds
they dissolve in ______
lipo-___
hydro-____
covalent
fats, membranes
philic
phobic
polar molecules have polar bonds
dissolve in _____
lipo-_____
hydro-____
h2o urine blood phobic philic
polar groups are not soluble in fat because there is no attraction between _____
the C and H bonds
amine and alcohol/hydroxy _____ groups
polar
___ # of C atoms to each polar group
4
ionic groups are ____
charged (pos or neg)
polar amines can be converted into an ionic ammonium by adding a _____ ion from ____
hydrogen
acid
lipophilic is referred to as____ ____ form
passes through ____
free base
BBB
the ___ is the value determined when the pH is half amine and half ammonium
pKa
when pH is less than pKa it is _____ form
ammonium ion
when pH is greater than pKa it is ____ form
amine
drugs with pKa close to 7.4 will be in what form?
both amine and ammonium
7.4 is physiological pH
topical LOCAL anesthetics will be almost completely in ____ form, so they dissolve thru membranes but do not spread out in tissues
amine
the ammonium ion form of the drug is a ____
solid
which form has a longer shelf life?
ammonium ion (solid)
the amine form of the drug is a ____
liquid
oral drugs are given in the ____ form
ammonium ion
enteric coated pills dissolve in the ___ ____
small intestine
______ ______drugs dissolve at different rates with a longer life
sustained release
Parenteral administrations of drugs include::
IV, IM, subcutaneous
Topical drugs are in the ____ form in order to pass through membranes
amine
rectal suppository is best for people who:
can’t swallow
the best way to have precise dosing is giving a drug ___
IV
drugs pass from blood vessels into tissues by slipping between ____ ____ cells
smooth muscle
____ ____ in capillary walls require that drugs dissolve through the membrane or are transported by proteins
tight junctions
tight junctions are the basis for the ____ ____ ____
ammonium ion forms cannot pass through tight junctions
blood brain barrier
phase 1 of drug metabolism uses the enzyme _____ _____
and it adds __ groups to non-polar molecules to make them polar
cytochrome P450
OH
phase 2 of drug metabolism uses the enzyme ___ _____ and adds ____ ____ to the molecule to make it water soluble and ready for excretion
glucuronyl transferase
glucuronic acid
a family of close related enzymes is called:
isozymes
loratidine is metabolized into ________ which is responsible for its activity
desloratidine
inactive drugs that are metabolized into the active form are called: ___ ____
pro dugs
the time required for 1/2 of a drug to be inactivated by the body:
half life
the rate of drug excretion depends on:
1.
2.
rate of drug metabolism
rate of excretion by kidneys
area on a graph between the toxic concentration and the minimum effective concentration: ____ ____
want it to be large
therapeutic range
examples of when someone should be given a lower dose
newborns, geriatrics, kidney disease
Lethal dose for 50% of population / effective dose for 50% = _____ ______
therapeutic index
factors that affect bioavailability:
taken on empty stomach or with food
taken with +2 or +3
constipation or diarrhea
