PCOL 350 ADME FINAL EXAM STUDY
GUIDE WITH COMPLETE SOLUTIONS
Idiosyncratic reactions to a xenobiotic such as an immune reaction, describe a
genetically determined predisposition to toxicity or resistance. - Correct Answers -true
one of the fundamental functions of toxicology is to characterize the relationship
between the dose of the agent and the response - Correct Answers -true
the dosage of a drug or toxicant that induces death in 50% of the treated animals is
referred to as - Correct Answers -lethal dose 50, LD50
3+4=7 is an example of - Correct Answers -additive drug effect
most drugs are xenobiotics and thus become toxicants at high enough doses - Correct
Answers -true
0+4=20 is and example of - Correct Answers -potentiation drug effect
the therapeutic index (TI) - Correct Answers -is quantified by diving the toxic dose (TD)
by the lethal dose (LD)
some agents exhibit a non-sigmoidal (S-shaped) dose-response relationship where
toxicity is observed at low and high doses. this is an example of - Correct Answers -
hormesis
active transport is characterized by - Correct Answers -- movement of chemicals against
concentration gradients
-selectivity for which molecules are transported
increased lipid solubility enhances the rate of penetration of toxicants into the CNS -
Correct Answers -true
ibuprofen (advil) would be - Correct Answers -absorbed in the stomach by passive
diffusion
plasma protein binding of drugs affects - Correct Answers -- the amount of free drug
- receptor binding of the drug
- the kinetics (half-life) of the drug
,tissue/organ distribution of drugs is determined by - Correct Answers -blood flow to the
tissue/organ
drug metabolites that appear in the urine via the kidney can be - Correct Answers --
filtered by the glomerulus
- secreted by renal tubular cells
- transported by active transport
enterohepatic recirculation results in drugs/metabolites - Correct Answers -- having a
longer half-life
- being broken down (metabolized) and reabsorbed in the intestines and returned to the
liver
which of the following is a potential advantage to using a prodrug in therapy - Correct
Answers -- the prodrug is more resistant to stomach acid
- use o f the prodrug may reduce adverse effect(s)
- biotransformation processes may convert the prodrug to an active drug in the target
tissue
- the prodrug may have better delivery to target tissues
metabolites of aspirin are shown. the product of reaction "A" is the result of _________
activity - Correct Answers -hydrolysis by a carboxyl esterase
metabolites of aspirin are shown. the product of reaction "B" is the result of _________
activity - Correct Answers -glucuronidation
metabolites of aspirin are shown. the product of reaction "C" is the result of _________
activity - Correct Answers -amino acid conjugation
metabolites of aspirin are shown. the product of reaction "D" is the result of _________
activity - Correct Answers -CYP hydroxylation
propranolol is a commonly used anti-hypertensive medication that undergoes Phase 1
and Phase 2 metabolism. What is the enzyme that catalyzes reaction "A" - Correct
Answers -CYP
propranolol is a commonly used anti-hypertensive medication that undergoes Phase 1
and Phase 2 metabolism. What is the enzyme that catalyzes reaction "B" - Correct
Answers -UDP-glucuronosyltransferase which adds glucuronide in phase 2 reactions
carbamazepine is an inducer of CYP3A4. in the following carbamazepine exposure, the
elimination of CYP3A4 substrates could be - Correct Answers -increased due to
CYP3A4 induction
in the liver hepatocyte, the primary site of phase 1 biotransformation is the - Correct
Answers -endoplasmic reticulum (ER)
, delta9-THC is metabolized to 11-hydroxy delta9-THC by - Correct Answers -a
cytochrome 450 (CYP)
aging has been shown to - Correct Answers -- decrease the dose required for some
drugs
- decrease the biotransformation of drugs
when given concurrently, the antibiotic drug, erythromycin, can inhibit the
biotransformation of terfenadine, and allergy medication. this occurs because - Correct
Answers -they are competing for the same biotransformation enzyme systems
because erythromycin inhibits the biotransformation of terfenadine - Correct Answers --
the half-life of terfenadine is increased
- the plasma concentration of terfenadine is increased
troglitazone was a promising antidiabetic drug that was eventually withdrawn from the
market due to its potential to cause liver injury. it is initially rapidly biotransformed by
phase 2 systems, which would include - Correct Answers -glucuronidation
which of the following is not added to xenobiotics in phase 2 biotransformation reactions
- Correct Answers -hydroxyl groups
in order for enterohepatic recirculation of a drug to occur - Correct Answers -- the gut
microbiome must metabolize the drug back to its original lipophilic form
- at least some of drug must be excreted via the bile
in the metabolic steps shown above, the first step would be performed by - Correct
Answers -an amidase
in the metabolic steps shown above, the second step would be performed by - Correct
Answers -dealkylation by CYP
in the metabolism of zolpidem shown above, the methyl group can be converted to a
carboxyl group by the action - Correct Answers -- CYP hydroxylation, followed by a
second round of CYP oxidation to an aldehyde, and then aldehyde dehydrogenase
- CYP hydroxylation followed by alcohol dehydrogenase and then aldehyde
dehydrogenase
the kidney can - Correct Answers -- filter and secrete drugs into the urine
- bioconcentrate drugs in the urine
- use active transport to collect drug metabolites in the filtrate
redistribution and elimination can decrease the pharmacological effect of a drug
because - Correct Answers -it can decrease drug concentration at the target receptor
GUIDE WITH COMPLETE SOLUTIONS
Idiosyncratic reactions to a xenobiotic such as an immune reaction, describe a
genetically determined predisposition to toxicity or resistance. - Correct Answers -true
one of the fundamental functions of toxicology is to characterize the relationship
between the dose of the agent and the response - Correct Answers -true
the dosage of a drug or toxicant that induces death in 50% of the treated animals is
referred to as - Correct Answers -lethal dose 50, LD50
3+4=7 is an example of - Correct Answers -additive drug effect
most drugs are xenobiotics and thus become toxicants at high enough doses - Correct
Answers -true
0+4=20 is and example of - Correct Answers -potentiation drug effect
the therapeutic index (TI) - Correct Answers -is quantified by diving the toxic dose (TD)
by the lethal dose (LD)
some agents exhibit a non-sigmoidal (S-shaped) dose-response relationship where
toxicity is observed at low and high doses. this is an example of - Correct Answers -
hormesis
active transport is characterized by - Correct Answers -- movement of chemicals against
concentration gradients
-selectivity for which molecules are transported
increased lipid solubility enhances the rate of penetration of toxicants into the CNS -
Correct Answers -true
ibuprofen (advil) would be - Correct Answers -absorbed in the stomach by passive
diffusion
plasma protein binding of drugs affects - Correct Answers -- the amount of free drug
- receptor binding of the drug
- the kinetics (half-life) of the drug
,tissue/organ distribution of drugs is determined by - Correct Answers -blood flow to the
tissue/organ
drug metabolites that appear in the urine via the kidney can be - Correct Answers --
filtered by the glomerulus
- secreted by renal tubular cells
- transported by active transport
enterohepatic recirculation results in drugs/metabolites - Correct Answers -- having a
longer half-life
- being broken down (metabolized) and reabsorbed in the intestines and returned to the
liver
which of the following is a potential advantage to using a prodrug in therapy - Correct
Answers -- the prodrug is more resistant to stomach acid
- use o f the prodrug may reduce adverse effect(s)
- biotransformation processes may convert the prodrug to an active drug in the target
tissue
- the prodrug may have better delivery to target tissues
metabolites of aspirin are shown. the product of reaction "A" is the result of _________
activity - Correct Answers -hydrolysis by a carboxyl esterase
metabolites of aspirin are shown. the product of reaction "B" is the result of _________
activity - Correct Answers -glucuronidation
metabolites of aspirin are shown. the product of reaction "C" is the result of _________
activity - Correct Answers -amino acid conjugation
metabolites of aspirin are shown. the product of reaction "D" is the result of _________
activity - Correct Answers -CYP hydroxylation
propranolol is a commonly used anti-hypertensive medication that undergoes Phase 1
and Phase 2 metabolism. What is the enzyme that catalyzes reaction "A" - Correct
Answers -CYP
propranolol is a commonly used anti-hypertensive medication that undergoes Phase 1
and Phase 2 metabolism. What is the enzyme that catalyzes reaction "B" - Correct
Answers -UDP-glucuronosyltransferase which adds glucuronide in phase 2 reactions
carbamazepine is an inducer of CYP3A4. in the following carbamazepine exposure, the
elimination of CYP3A4 substrates could be - Correct Answers -increased due to
CYP3A4 induction
in the liver hepatocyte, the primary site of phase 1 biotransformation is the - Correct
Answers -endoplasmic reticulum (ER)
, delta9-THC is metabolized to 11-hydroxy delta9-THC by - Correct Answers -a
cytochrome 450 (CYP)
aging has been shown to - Correct Answers -- decrease the dose required for some
drugs
- decrease the biotransformation of drugs
when given concurrently, the antibiotic drug, erythromycin, can inhibit the
biotransformation of terfenadine, and allergy medication. this occurs because - Correct
Answers -they are competing for the same biotransformation enzyme systems
because erythromycin inhibits the biotransformation of terfenadine - Correct Answers --
the half-life of terfenadine is increased
- the plasma concentration of terfenadine is increased
troglitazone was a promising antidiabetic drug that was eventually withdrawn from the
market due to its potential to cause liver injury. it is initially rapidly biotransformed by
phase 2 systems, which would include - Correct Answers -glucuronidation
which of the following is not added to xenobiotics in phase 2 biotransformation reactions
- Correct Answers -hydroxyl groups
in order for enterohepatic recirculation of a drug to occur - Correct Answers -- the gut
microbiome must metabolize the drug back to its original lipophilic form
- at least some of drug must be excreted via the bile
in the metabolic steps shown above, the first step would be performed by - Correct
Answers -an amidase
in the metabolic steps shown above, the second step would be performed by - Correct
Answers -dealkylation by CYP
in the metabolism of zolpidem shown above, the methyl group can be converted to a
carboxyl group by the action - Correct Answers -- CYP hydroxylation, followed by a
second round of CYP oxidation to an aldehyde, and then aldehyde dehydrogenase
- CYP hydroxylation followed by alcohol dehydrogenase and then aldehyde
dehydrogenase
the kidney can - Correct Answers -- filter and secrete drugs into the urine
- bioconcentrate drugs in the urine
- use active transport to collect drug metabolites in the filtrate
redistribution and elimination can decrease the pharmacological effect of a drug
because - Correct Answers -it can decrease drug concentration at the target receptor
