dEq

Predifined PK/PD models

This module allows to simulate PK/PD models using the differential equations. The following predefined PK/PD models are available in PKMP.

PK Models	PD Models	Single dose	Multiple dose	Cp or Cpe1
Extravascular	Emax Emax with baseline effect Sigmoid Emax Sigmoid Emax with baseline effect Inhibition Emax Inhibition Emax with baseline effect Inhibition sigmoid Emax Inhibition sigmoid Emax with baseline effect	Yes	Yes	Yes
1CBM
2CBM
IV Bolus
1CBM
2CBM
3CBM
IV Infusion
1CBM
2CBM
3CBM

1Cp and Cpe are plasma and effect compartment concentrations, respectively.

Integration methods available are:

• Runge-Kutta (4th order) or,
• Runge-Kutta-Cash-Karp or,
• Runge-Kutta-Fehlberg

The following is an example of a PK/PD simulation.

User Defined Differential Equations Simulation

This module allows simulation of functions that solve initial value problems of a system of first-order ordinary differential equations. The following provides guidance on how to write differential equations and functions.

1. Enter the equations, time frame, step size, and unit of time and press Next button.




 
2. Identify the compartments and parameters and enter their units and press Submit button.




 
3. Enter the parameter values and dose(s) in the compartment. Doses can be given as bolus or infusion single or multiple dose and combination of them.




 
4. Results are displayed with equations, parameters, and compartment values over the simulation time frame.




 
5. Simulation graph for the compartment is displayed.




 
6. Diagnostics of the run are displayed.




 

  Note: In the diagnostics rtol is relative error tolerance and atol is absolute error tolerance.