Section FOUR. 15 + 19 + 10 = 44 points
Show all your work for full credit. All material not deleted or crossedout will be considered for grading. Do NOT use any linear or semilog regression functions/features that might be on the calculator that you use during this exam.
Q4.1 Version A, D, Q4.2 Version B, Q4.3 Version C (15 points) Assuming a one compartment linear pharmacokinetic model, with kel = 0.16 hr1 and V = 78 L, calculate the expected plasma concentration at 24 hours after the following IV bolus dose schedule: 200 mg at time 0 hr; 300 mg at 6 hr; 300 mg at 18 hours. 


Q4.2 Version A, D, Q4.3 Version B, Q4.1 Version C. (19 points) Calculate an appropriate dosing regimen for the following male patient; age = 67 years, weight = 74 kg, serum creatinine = 1.8 mg/ 100 ml (mg %). With this drug the kel is a function of creatinine clearance and previously determined values include: kel = 0.05 hr1 with CLCr = 15 ml/min and kel = 0.12 hr1 with CLCr = 60 ml/min. The apparent volume of distribution was 0.45 L/kg. Develop a dosing regimen to keep the peak concentration close to but below 6 µg/ml and the trough concentration below 1 µg/ml. Adjust tau to an appropriate value that is a multiple of 4 hours. Round doses to the nearest, appropriate 5 mg and calculate the expected maximum and minimum plasma concentrations. 


Q4.3 Version A, D, Q4.1 Version B, Q4.2 Version C. (10 points) A drug is to be given orally every twenty four hours to achieve an average concentration of 30 mg/L. Calculate the dose (F = 0.80) required if t1/2 = 12 hours and V = 32 L. Round your answer to the nearest 25 mg. Estimate the average, peak and trough concentrations after steady state is reached, using the rounded dose. 
