T01-10) Random from these types

50. Pharmacokinetics 50.2) Plasma concentrations over time 50.2.1) Plasma concentrations over time

T01: Later plasma concentration Normal 1


Total tried:       Correct:       Wrong:

A 189 Kg patient was intravenously administered a drug. The plasma concentration was found to be 4.42 mg/L, when the blood was first collected. If the drug follows a first order elimination and the plasma half-life of the drug is `28.88 \quad h`, then determine the plasma concentration after 0.5 hours.


Click on the button below to see the answer and explanations


Notice: Undefined variable: input_value1 in /home/jshzub/web/rxcal.org/public_html/practice/practice/includes/body.php on line 220
lb equals 4.367 mg/L kg

    For a first order process,
    `C_{t}=C_{0}×e^(-kt)`
    In the question, k is not provided, but we can derive it from the equation below:
    `k=0.693/t_{½}=0.693/(28.88 h)=0.024 h^{-1}`.
    Plugging the values in this equation, we get:
    `C_{t}=4.42 × e^(- 0.024 × 0.5)`
    `∴ C_{t}=4.367`
    Thus, the later concentration is: 4.367 mg/L. (Ans).


Notice: Undefined index: TOTALTRY in /home/jshzub/web/rxcal.org/public_html/practice/practice/includes/body.php on line 675