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#1




Calculate the drug loading dose?
Can't remember if this was posted but here goes:
At a target concentration of 7.5 mg/L of theophyline is required by a 60kg patient. What is the loading dose given the following: Vd= 0.5 L/kg Cl= 0.04 L/kg/hr t1/2= 9.3 hrs 
#2




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LD=CpxVd/F LD=7.5x0.5=3.75mg/Kg=225mg
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#3




Loading dose= Vd x Cp / f
lets assume bioavailability is 1 Loading dose = 0.5 x 7.5 / 1 = 3.75 mg so loading dose = 3.75 mg according to weight 3.75 x 60 = 225 mg
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#4




thasts right but am confused here pls explain this question one for me; Q:if drug is known to be distributed into TBW, what dose (mg) is needed to obtain an initial plasma level of 5mg/L in patient weighing 70kg? a)210 b)150 c)110 d)50 e)35
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#5




Quote:
A)210 This is loading dose question. since the patient weighs 70kg and 60% TBW,he has 42 L (70L X 60%) Of TBW. NOW LD = Vd x Cp LD = 42L X 5mg/L = 210mg
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#6




Quote:
Loading dose = Cp X Vd /F = 7.5 mg/L X 0.5 L/Kg / 1 = 3.75 mg / Kg Now times this by 60 Kg to get rid of Kg. 3.75 mg/Kg X 60 Kg = 225 mg is my answer. Don't know if I'm right or wrong. 
#7




Quote:
Please Nena help me with this one, im so confused why do you multiply 70 by the porcentage of water? please someone explain, im stuck here 
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