Question

DO NOT ANSWER QUESTION 10. I only need question 9 and 11

plz, answer all questions clearly and correctly. i am begging you

9. If the amount of drug in the body declines from 100% of the dose (IV bolus injection) to 25% of the dose in 8 hours, what is the elimination half-life for this drug? (Assume first-order kinetics.) (10) A drug has an elimination half-life of 8 hours and follows first-order elimination kinetics. If a single 600-mg dose is given to an adult female patient (62 kg) by rapid IV injection, what percent of the dose is eliminated (lost) in 24 hours assuming the apparent Vis 400 mL/ kg? What is the expected plasma drug concen- tration (C) at 24 hours postdose? For drugs that follow the kinetics of a one- compartment open model, must the tissues and plasma have the same drug concentration? Why?

Answer 1

9) Half life of the drug is defined as the time interval in which the drug concentration becomes half of the original.,I.e. 100% of the drug becomes 50%.

In 1st half life ,100% becomes 50%

In 2nd half life ,50% becomes 25%.

Since in 8 hours, drug concentration became 25%, 2 t1/2 = 8 hours

T1/2 = 4 hours

11)One-compartment open model means the whole body acts like one unoform compartment and the drug can freely enter and leave the body.So in that case,the tissues and plasma have the same drug concentration because the drug can freely diffuse between the plasma and the tissues.