Q 3.4 (10 points) A drug is known to follow one compartment pharmacokinetics. The elimination rate constant in patients with normal renal function is approximately 0.39 hr^-1, the apparent volume of distribution is 35.7L, and the value of fe is 0.35. Assume that metabolism is unaffected by changes in renal function. Calculate the expected elimination half-life in patients with only 30% of normal renal function.

kel = 0.39 hr^-1 (t_1/2 = 1.78 hr)

fe = 0.35

ke = 0.1365 hr^-1

km = 0.39 - 0.1365 = 0.2535 hr^-1

ke(patient) = ke x 0.3 = 0.04095 hr^-1

km(patient) = 0.2535 hr^-1

kel(patient) = 0.04095 + 0.2535 = 0.294 hr^-1

t_1/2 (patient) = 2.36 hr