3. A promising new drug is being evaluated in human trials. Based on preliminary human tests, this drug is most effective when plasma levels exceed 30 mg/L.  Measurements from preliminary tests indicate the following human pharmacokinetic parameter values:  t1/2,elim = 4.6hr, t1/2,abs = 0.34hr, VD = 0.29 L/kg, Foral = 72%.  Based on these parameters, estimate the following if a 49 kg woman were to receive a 1000mg oral dose of this drug: (a) Estimate the plasma concentration of the drug at 1hr, 6 hr, and 20hr after taking the drug ( Concentration estimate) (b) Estimate the time for maximum plasma concentration (tmax).  (c) Estimate the maximum plasma concentration (Cmax).  (d) Estimate the time at which the plasma level first rises above 30 mg/L.  (Note this is a trial and error problem where you must guess a time, plug it into the concentration equation, and determine if it is close to 30 mg/L.  Hint:  based on part (a) it should be apparent that the answer is less than 1hr.)  (e) Estimate the time at which the plasma level finally drops to 30 mg/L.  (Note that this again is a trial and error problem, as in part (d).  Hint:  based on (a) the answer should be between 1 and 6hr.)  (f) Estimate the total time that this woman’s plasma level is expected to be above the concentration of 30 mg/L.

3. A promising new drug is being evaluated in human trials. Based on preliminary human tests, this drug is most effective when plasma levels exceed 30 mg/L.  Measurements from preliminary tests indicate the following human pharmacokinetic parameter values:  t1/2,elim = 4.6hr, t1/2,abs = 0.34hr, VD = 0.29 L/kg, Foral = 72%.  Based on these parameters, estimate the following if a 49 kg woman were to receive a 1000mg oral dose of this drug:

(a) Estimate the plasma concentration of the drug at 1hr, 6 hr, and 20hr after taking the drug ( Concentration estimate)

(b) Estimate the time for maximum plasma concentration (tmax). 

(c) Estimate the maximum plasma concentration (Cmax). 

(d) Estimate the time at which the plasma level first rises above 30 mg/L.  (Note this is a trial and error problem where you must guess a time, plug it into the concentration equation, and determine if it is close to 30 mg/L.  Hint:  based on part (a) it should be apparent that the answer is less than 1hr.) 

(e) Estimate the time at which the plasma level finally drops to 30 mg/L.  (Note that this again is a trial and error problem, as in part (d).  Hint:  based on (a) the answer should be between 1 and 6hr.) 

(f) Estimate the total time that this woman’s plasma level is expected to be above the concentration of 30 mg/L.