Practice question set drug absorption and biotransformation

Medical Pharmacology Pharmacokinetic Practice
Questions
1. Principal organ for biotransformation of drugs:
kidney
lung
liver
skin
2. Factors that affect first pass pulmonary effect
magnitude
spontaneous respiration
control ventilation
apnea
none of the above
3. Half-life = time required to decrease in other drug in
the body by 50% during elimination.
Assumption(s):
single body compartment size =apparent
volume of distribution
blood or plasma is considered in equilibrium
with a total apparent volume of distribution
4. Capacity-limited elimination
aspirin
saturable process
both
neither
5. Bioavailability 65% of dose
lidocaine (Xylocaine)
fentanyl (Sublimaze)
propranolol (Inderal)
alfentanil (Alfenta)
meperidine (Demerol)
7. glucuronidation:
morphine
epinephrine
dopamine (Intropin)
histamine
8. Localization of mixed function oxidase system:
smooth endoplasmic reticulum membranes
rough endoplasmic reticulum membranes
9. Parent drug is altered by introducing or exposing a
functional group such as -OH or NH2
Phase I
Phase II
10.
Important microsomal enzyme/enzymes for
drug biotransformation
flavoprotein NADPH cytochrome P450
reductase
cytochrome P450
both
neither
11.
Number of half-lives required to go from one
steady-state to another:
1
2
4
8
12.
Drugs poorly extracted by the liver:
digitoxin (Crystodigin)
diazepam (Valium)
meperidine (Demerol)
chlorpropamide (Diabinese)
13.
Most important organ for unchanged drug/drug
metabolite elimination
liver
lung
kidney
none of the above
14.
Drug-plasma protein binding
most drugs are bound to plasma protein
alpha1-acid glycoprotein increases
following surgery, myocardial infarction, and
in response to chronic pain
renal failure may affect drug bound fraction
drug-plasma albumin binding is typically
very selective
15.
The definition of “context-sensitive” halftime
is the length of time required for drug plasma
concentration to fall 50% after continuous infusion
true
false
16.
Termination drug action
usually by biotransformation followed by
excretion
sometimes by redistribution from the drug
site of action to other tissues or sites
both
neither
17.
Factor(s) influencing clearance (CL):
elimination rate constant
volume of distribution
both
neither
18.
Property/properties of phase II conjugates:
relatively nonpolar
generally biologically active
rapidly excreted in the urine
all of the above
19.
Absorption rate proportional to the drug
concentration dissolved in the gastrointestinal tract
zero order
first order
neither
20.
Biotransformation: tends to convert a drug to a
more hydrophobic (lipophilic) metabolite
true
false
21.
Factor(s) influencing renal clearance:
carrier saturation
extent of drug-plasma protein binding
volume filtered in the glomerulus
blood flow
number of functional nephrons
22.
Glomerular filtration:important factors
extent of drug-protein binding
glomerular filtration rate
both
neither
23.
Factor(s) influencing the volume of
distribution:
patient’s gender
patient’s age
patient’s disease state
patient’s body composition
all the above
24.
Factor(s) which may change intrinsic drug
clearance:
smoking
dietary considerations
age
genetic factors
all the above
25.
Renal clearance
influenced by renal disease
affected by the number of functional
nephrons
altered by blood flow
all of the above
26.
Passive renal tubular reabsorption:
enhance lipid solubility favors excretion
renal tubule or reabsorption rate influenced
by rate of renal tubular urine flow
both
neither
27.
Drug mechanism/mechanisms which may
increase the amount of cytochrome P450 enzyme:
increased enzyme degradation rates
increase enzyme synthesis rate
both
neither
28.
Factor(s) affecting hepatic clearance:
extent of blood flow to the liver
extent of plasma protein bound drug
both
neither
29.
Factor(s) influencing drug half-life:
chronic renal failure
age
plasma protein binding
none of the above
30.
Large volumes of distribution:
associated with chloroquine (Aralen)
suggests minimal tissue binding
both
neither
31.
Phase II characteristics: parent compound
functional group linkages with
sulfate
glucuronic acid
acetate
amino acids
glutathione
32.
Factor/factors which may reduce drug
bioavailability:
exposure to digestive enzymes
gastric acid instability
absence of intestinal flora (bacteria)
first pass effect
33.
Drug(s) with high extraction by the liver:
imipramine (Tofranil)
meperidine (Demerol)
propranolol (Inderal)
amitriptyline (Elavil, Endep)
isoniazid (INH)
34.
Drugs which exhibit clearances > 6 ml/min./kg
diltiazem (Cardiazem)
verapamil (Isoptin, Calan)
lidocaine (Xylocaine)
meperidine (Demerol)
morphine
…