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PA 2306- MOD 7 > Pharmocokinetics > Flashcards

Flashcards in Pharmocokinetics Deck (17)
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1
Q

What are the fates of drug distribuition in the body

A
  • Binding and storage in tissues
  • Biotransformation (into metabolites)
  • Metaboluites in systematic circulation
  • Renal excretion
  • Biliary excretion
2
Q

How does protein bind to drugs (method)

A

Non-covelent binding (also reverible to maintain bound:free)

3
Q

How can drug interactions be explained due to protein binding and ex

A

2 drugs may both bind to albmin but one may displace the other off of it increasing the free concentration of the drug causing a increased phamo effect (as + morophine)

-Low albumin can also cause this

4
Q

What is the isoelectric point and what does it indicate

A

Ph5= 100 pos and 100 neg charges

5
Q

What can increased billirubin but low albumin cause

A

increased conc of free biliirubin causing jaudice

6
Q

What causes kernicterus

A

failled billirubin tx where it will actially migrate to brain tissue staining it

7
Q

How will non polar vs charged molecules move thru body water

A

charged molecules will only be in extracellular space where non polar will distribute thru total body water

8
Q

What is the calculation for conc of a drug + apparent volume of distribution

A

Concentration (drug in plasma)= mass (ammount of drug)/ Volume (of distribution)

Vd= mass of drug given/ conc in plasma

9
Q

For meaningful interpretation of the apparent volume of distribution you should

A

Should be evaluated from the conc of the free unbound drug

10
Q

What is half life

A

is the time elapsed for its plasma conc to be reduced by 50%

11
Q

How much longer is the effect of the drug extended when dose it doubled

A

extended by one half life

12
Q

how many hal lifes does it take to reach steady state in oral administration

A

5

13
Q

What is the wash out period and how long does it take to get back to a drug conc of zero after stopping IV

A

wash out period- when administration is stopped

-5 half lives to reach zero

14
Q

When you repetedly administer an oral drug to steady state what will you see

A

Will see a rise and fall in conc slow and steady up until steady state

15
Q

How many half lives will it take to reach steady state again if you double dose

A

5

16
Q

how to asses oral bioavaility compared to IV (equation)

A

bioavailality= (AUC oral/AUC IV) * 100

auc=area under curve

17
Q

What is the formula for desired dose

A

volume of distribution* desired dose/ bioavailability

Bioavail= 1 in IV