HNG 540 EXAM 1 EXAM QUESTIONS & ANSWERS
What are the four concepts associated with pharmacokinetics? - Answers -Absorptions
Metabolism
Distribution
Elimination
Pharmacokinetics - Answers -what the body does to the drug
pharmacodynamics - Answers -what the drug does to the body
protein binding - Answers -the attachment of a drug molecule to a plasma or tissue
protein, effectively making the drug inactive but also keeping it within the body
Bioavailability - Answers -A measure of the extent of drug absorption for a given drug
and route (from 0% to 100%).
Advantage of minimal protein binding - Answers -better tissue penetration as there is
more free drug available
disadvantage of minimal protein binding - Answers -excreted much faster than a
medication with a higher binding level
What does protein binding effect? - Answers -distribution, metabolism, and elimination
Disadvantage of strongly bound protein drugs - Answers -will have lower concentration
of free form drugs available for interaction, leading to longer duration of action and low
rates of elimination
True/False the unbound form of a drug cannot exert any effect - Answers -False - the
remaining unbound portion of a drug is the ONLY portion that will exert any effect
A drug displays 60% protein binding? What percentage will exert an effect? - Answers -
40% of the drug is free/unbound, meaning that only that 40% will have an effect
What needs to be considered protein binding wise, when prescribing medications? -
Answers --patients serum protein levels
- dose of medication
Why must dosing be considered when prescribing medications in relation to protein
binding? - Answers -this should be considered to ensure maximum drug amount is
available to have an effect on the body
What factor can influence gastric absorption when a drug is being administered orally? -
Answers -Lipid solubility
, What type of drugs tend to be absorbed more efficiently in the GI tract? - Answers -
lipophilic drugs
Why do lipophilic drugs get absorbed more efficiently in the GI tract and stomach? -
Answers -this is due to cell membranes in the GI tract being composed of lipids, allows
these drugs to cross more freely
first pass metabolism - Answers -the substance degradation of an orally administered
drug caused by enzyme metabolism in the liver before the drug reaches the systemic
circulation
True/False only PO medications undergo first pass metabolism - Answers -False; all
drugs regardless of route of administrations must pass through the liver before reaching
its target tissues and having therapeutic effects; many drugs are not active until they
reach the liver
What is the process of a PO drug going through first pass? - Answers -drug
administered -> drug absorbed into the GI mucosa then to the blood stream-> portal
circulation -> Liver metabolizes -> biotransformations -> elimination
portal circulation - Answers -a system of veins from GI tract to liver
Liver metabolism (biotransformation) - Answers -metabolic reactions occurs mediated
by enzymes changing structure to be more water soluble allowing for ease of
elimination
Phase I enzymes - Answers -CYP450
What is phase I metabolism? - Answers -oxidize, reduce and hydrolyze the drug;
functional groups intriduced making the drug more polar (water soluble) but not
necessarily inactive (otherwise drugs cannot be excreted and increased risk for toxicity)
Phase II metabolism - Answers -drugs/phase I metabolites are conjugated with
endogenous compounds (like amino acids/sulfates) increasing water solubility and
facilitating elimination
what happens to drugs after first pass? - Answers -drug is released into systemic
circulation then carried to various tissues and organs to exert effect
therapeutic action - Answers -drug reaches target tissues and interacts with receptors
to produce desired effects
How are drugs eliminated? - Answers -renal excretions (glomerulus via urine), biliary
excretion (biles into digestive tract), and other ways depending on the drug (skin, saliva
and breast milk)
What are the four concepts associated with pharmacokinetics? - Answers -Absorptions
Metabolism
Distribution
Elimination
Pharmacokinetics - Answers -what the body does to the drug
pharmacodynamics - Answers -what the drug does to the body
protein binding - Answers -the attachment of a drug molecule to a plasma or tissue
protein, effectively making the drug inactive but also keeping it within the body
Bioavailability - Answers -A measure of the extent of drug absorption for a given drug
and route (from 0% to 100%).
Advantage of minimal protein binding - Answers -better tissue penetration as there is
more free drug available
disadvantage of minimal protein binding - Answers -excreted much faster than a
medication with a higher binding level
What does protein binding effect? - Answers -distribution, metabolism, and elimination
Disadvantage of strongly bound protein drugs - Answers -will have lower concentration
of free form drugs available for interaction, leading to longer duration of action and low
rates of elimination
True/False the unbound form of a drug cannot exert any effect - Answers -False - the
remaining unbound portion of a drug is the ONLY portion that will exert any effect
A drug displays 60% protein binding? What percentage will exert an effect? - Answers -
40% of the drug is free/unbound, meaning that only that 40% will have an effect
What needs to be considered protein binding wise, when prescribing medications? -
Answers --patients serum protein levels
- dose of medication
Why must dosing be considered when prescribing medications in relation to protein
binding? - Answers -this should be considered to ensure maximum drug amount is
available to have an effect on the body
What factor can influence gastric absorption when a drug is being administered orally? -
Answers -Lipid solubility
, What type of drugs tend to be absorbed more efficiently in the GI tract? - Answers -
lipophilic drugs
Why do lipophilic drugs get absorbed more efficiently in the GI tract and stomach? -
Answers -this is due to cell membranes in the GI tract being composed of lipids, allows
these drugs to cross more freely
first pass metabolism - Answers -the substance degradation of an orally administered
drug caused by enzyme metabolism in the liver before the drug reaches the systemic
circulation
True/False only PO medications undergo first pass metabolism - Answers -False; all
drugs regardless of route of administrations must pass through the liver before reaching
its target tissues and having therapeutic effects; many drugs are not active until they
reach the liver
What is the process of a PO drug going through first pass? - Answers -drug
administered -> drug absorbed into the GI mucosa then to the blood stream-> portal
circulation -> Liver metabolizes -> biotransformations -> elimination
portal circulation - Answers -a system of veins from GI tract to liver
Liver metabolism (biotransformation) - Answers -metabolic reactions occurs mediated
by enzymes changing structure to be more water soluble allowing for ease of
elimination
Phase I enzymes - Answers -CYP450
What is phase I metabolism? - Answers -oxidize, reduce and hydrolyze the drug;
functional groups intriduced making the drug more polar (water soluble) but not
necessarily inactive (otherwise drugs cannot be excreted and increased risk for toxicity)
Phase II metabolism - Answers -drugs/phase I metabolites are conjugated with
endogenous compounds (like amino acids/sulfates) increasing water solubility and
facilitating elimination
what happens to drugs after first pass? - Answers -drug is released into systemic
circulation then carried to various tissues and organs to exert effect
therapeutic action - Answers -drug reaches target tissues and interacts with receptors
to produce desired effects
How are drugs eliminated? - Answers -renal excretions (glomerulus via urine), biliary
excretion (biles into digestive tract), and other ways depending on the drug (skin, saliva
and breast milk)
