Simple answers only and allocate what answer is which.

You are developing a dosage regimen for an 85kg patient who is 1.8m tall. The drug (to be given by IV injection, having a molecular weight of 350 but administered as the sodium salt, MW 372) has the following pharmacokinetic and therapeutic parameters: VD: 0.50L/kg t1/2:180 minutes Therapeutic range: 515 microgram/mL Toxic Level: 20 microgram/mL Your colleague has proposed a multi-dose regimen as follows: Initial IV dose of 5mg/kg has been proposed with repeat dosage of 3mg/kg every 3 hours. You may consider the drug to be non-protein bound. a. Calculate the initial plasma concentration after the first dose (1 mark) b. Calculate plasma concentrations of the drug immediately before the second and third doses ( 2 marks) c. The first dose was larger than subsequent doses. Why? (1 mark) d. Discuss the suitability of this drug regimen (comment on therapeutic efficacy, toxicity and any other factors you deem relevant) (2 marks)