Calculation of Drug Concentration

Non-Uniform Multiple IV Bolus Dose Regimen

A patient is started on a drug at an IV bolus dose of 50 mg at time zero, 250 mg at 4 hours and 25 mg at 28 hours (makes no sense but a nice random regimen :- all times are from time zero). Calculate the drug concentration at a few of time points during the first three dosing interval. It might be useful if you sketch the expected data or dosing regimen (this sketch is not required for the homework exercise). Specifically calculate the concentration three hours after the first dose, two hours after the second dose and one hour after the third dose. Assume a one compartment linear model applies to this drug in this concentration range. The half-life and V for this drug in this patient (74.3 kg) are 2.6 hr and 0.35 L/kg, respectively.

NOTE: Clicking the button above
will prevent you getting credit for this problem

To get credit for this problem print this page, work the problem and

You will have one chance to submit your answers for this problem [# 481559259]. You can try the homework problem more than once with different data to improve your grade. Your highest score is recorded. After submitting your answers you can use the browser back arrow to get back here and see how the compuer worked the problem.

An equation:

Equation 25.4.1 Drug Concentration during a Multiple Dose Regimen (Non-Uniform Regimen)

where t is time since the first dose was given, d2 is the time when the second dose was given (since the first dose) and d3 is the time when the third dose was given (since the first dose). Remember to include two terms (exponential terms) after the second dose, three terms after the third dose, etc., when calculating total concentration after the second, third, and subsequent doses.

See also the section on the Superposition Principle

Last update: Sat 27 Jul 2024 08:10:10 pm

Privacy Statement - 25 May 2018

Material on this website should be used for Educational or Self-Study Purposes Only

iBook and pdf versions of this material and other PK material is available