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Old 04-12-2013
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Drug Drug Steady state Concentration

How long does it take drug X to get to steady state
(hours)? (Drug X has a half life of 6h, a Clearance of
5L/h and a rate of infusion of 10 mg/h )

1. 2
2. 3
3. 25
4. 30
5. 50

No idea how to answer this so if somebody could break it down step by step it would be much appreciated
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Old 04-12-2013
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4-5 half lives are required to achieve steady state with constant drug infusion

4. 30 (5x6h)
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Old 04-12-2013
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Default corect answr is d) 30

clinical steady state = 4 to 5 t1/2 life
about 5 half life it wil take to reach the steady state so
5x6=30hrs.

with initial dose 10mg and constant infusion rate:

1st half life=5mg/hr
3rd half life= 8.8mg/hr
5th half life=9.5mg/hr
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Last edited by neha_subh; 04-12-2013 at 12:12 PM.
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Old 04-12-2013
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Thank you! Cant believe it was that easy!
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