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The half-life of a drug is longest in which situation?
A. A small volume of distribution
B. A large volume of distribution
C. A high concentration of drug in the plasma
D. Low concentrations of the drug in organs and tissues
E. Less total drug is present
F. An oral drug is given more frequently
G. An oral drug is given in higher doses
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t1/2 = .7 Vd/Cl
therefore B is right
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g would happen in a zero order
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victor correct me
vd =dose/cocen
t1/2=is the time req for 50% of dose
vd changes with cocen ,keeping dose same,rt
t1/2 does not depend on dose,how much ever the dose is ,same time taken to make it half
while all this true in fist order
in zero order,t1/2 depends on dose,greater the dose more time taken to become 50%-bcozonly a constant amount is eleminated
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lisa, i understand your explanation and it makes alot of sense, but then, most of the drugs that undergo zero order kinetics, do so at high doses only eg salicylate
the que also did not state the drug, or if its zero or first order.
i may have chosen that ans assuming a first order elimination which is commoner.
may be att would want to clarify this for us or someone else who understands it.
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B is correct ans
high vol of distrubution
cos with high vol of distribution large amount of drug will be in body and less drug is available in plasma for excretion or metabolism to inactivde compound.therefore its half life will be greater.
