<prompt> A patient was given a 200 mg dose of a drug IV, and 100 mg was eliminated during the first 2 hours. If the drug follows first-order elimination kinetics, how much of the drug will remain 6 hours after its administration100 mg75 mg50 mg25 mg  <response>: One half of the dose is eliminated in the first 2 hours so its elimination half-life equals 2 hours. With the passage of each half-life the amount in the body or in the blood will decrease to 50 of a former level. Thus, at 6 hours after administration, 3 half-lives have passed: 1 200 mg to 100 mg, 2 100 mg to 50 mg, and 3 50 mg to 25 mg. Ref:- kd tripathi; pg num:-32 Plasma half-life:- 