PHCL 412 Quiz 1 Questions With Complete Solutions
Distribution
of drugs depends on, size of the organ, blood flow, solubility,
binding
Drugs are distributed in different phases
starting with high flow areas then low flow areas
Why is the blood brain barrier a challenge for drugs?
membranes have tight junctions which are hard to pass through
Vd volume of distribution
the volume that relates the amount of drug given to the body to
the plasma
amount of drug in the body/plasma drug concentration
How to calculate therapeutic dose?
Vd x Cp (plasma concentration)
Metabolism
how body changes the drug in order to eliminate it
Phase 1 metabolism
typically uses cytochrome P-450 family members to add or
expose a functional group on the drug making it more polar
Phase 2 metabolism
,conjugates a bulkier functional group onto the drug in order to
further increase water solubility and excretion
Excretion
enterohepatic circulation, conjugated drugs in the liver can be
carried in the bile into the gut for excretion. Most drugs excreted
through the urine by action of the kidneys
Zero-order kinetics
a fixed amount of drug can be handled at one time
linear
First-order Kinetics
a constant fraction of the drug is metabolized per unit of time
(more drug, faster metabolism)
Half life
time to excrete half of the drug. small half life=metabolized
quickly
How long does it take to reach steady state?
4-5 half lives
OTC vs Prescription drugs
-tend to have less side effects
-require less monitoring
What is the most common ingredient in OTC drugs?
acetaminophen, NSAIDS
What is analgesics?
, pain medications, acetaminophen, NSAIDS
cox2 inhibitors
Cox2
enzyme that causes the release of prostaglandins specifically
PGE2 which along with other inflammatory agents can increase
the sensitivity of nociceptors in the spine causing hyperalgesia
and allodynia
COX1 and COX2
both found circulating inflammatory cells so their blockade can
reduce inflammation
How does blocking cox enzyme inhibit fever?
blocking the effects of prostaglandins on the receptors on the
thermosensitive neuron in the hypothalamus
What does overdose on acetaminophen lead to?
liver toxicity
Asprin
acetylsalicylic acid
blocks pain, fever, but need higher dose to fight inflammation
blocks platelet aggregation in small doses
What is a complication with asprin?
causes increased HCl in the stomach which can lead to ulcers
Why should kids not take asprin?
Can cause Reye's disease
Distribution
of drugs depends on, size of the organ, blood flow, solubility,
binding
Drugs are distributed in different phases
starting with high flow areas then low flow areas
Why is the blood brain barrier a challenge for drugs?
membranes have tight junctions which are hard to pass through
Vd volume of distribution
the volume that relates the amount of drug given to the body to
the plasma
amount of drug in the body/plasma drug concentration
How to calculate therapeutic dose?
Vd x Cp (plasma concentration)
Metabolism
how body changes the drug in order to eliminate it
Phase 1 metabolism
typically uses cytochrome P-450 family members to add or
expose a functional group on the drug making it more polar
Phase 2 metabolism
,conjugates a bulkier functional group onto the drug in order to
further increase water solubility and excretion
Excretion
enterohepatic circulation, conjugated drugs in the liver can be
carried in the bile into the gut for excretion. Most drugs excreted
through the urine by action of the kidneys
Zero-order kinetics
a fixed amount of drug can be handled at one time
linear
First-order Kinetics
a constant fraction of the drug is metabolized per unit of time
(more drug, faster metabolism)
Half life
time to excrete half of the drug. small half life=metabolized
quickly
How long does it take to reach steady state?
4-5 half lives
OTC vs Prescription drugs
-tend to have less side effects
-require less monitoring
What is the most common ingredient in OTC drugs?
acetaminophen, NSAIDS
What is analgesics?
, pain medications, acetaminophen, NSAIDS
cox2 inhibitors
Cox2
enzyme that causes the release of prostaglandins specifically
PGE2 which along with other inflammatory agents can increase
the sensitivity of nociceptors in the spine causing hyperalgesia
and allodynia
COX1 and COX2
both found circulating inflammatory cells so their blockade can
reduce inflammation
How does blocking cox enzyme inhibit fever?
blocking the effects of prostaglandins on the receptors on the
thermosensitive neuron in the hypothalamus
What does overdose on acetaminophen lead to?
liver toxicity
Asprin
acetylsalicylic acid
blocks pain, fever, but need higher dose to fight inflammation
blocks platelet aggregation in small doses
What is a complication with asprin?
causes increased HCl in the stomach which can lead to ulcers
Why should kids not take asprin?
Can cause Reye's disease
