Zero-order steady state infusion

Starting with version 0.10.0, mrgsolve can implement dosing records calling for a zero-order infusion at steady state. Find out more in this blog post.

events
infusion
steady state
Author

Kyle Baron

Published

January 1, 2020

1 Introduction

Starting with version 0.10.0 (released October, 2019), mrgsolve can implement dosing records calling for a zero-order infusion at steady state. To do this, set rate to a non-zero value, amt to zero, and ss to 1.

2 Example

For a 10 mg/hr infusion at steady state

library(mrgsolve)
library(dplyr)

mod <- house(end = 72, delta = 0.1) %>% update(outvars = "CP")

mod <- param(mod, CL = 2)

dose <- ev(amt = 0, rate = 100, ss = 1, cmt = 2)

The dosing event looks like

dose
Events:
  time amt rate cmt evid ss
1    0   0  100   2    1  1

With CL set to 2, we expect the system to start out at 50

mrgsim(mod,dose,recsort = 3) %>% plot()

3 Notes

  • It is an error to include addl
  • You can model the rate
    • Set rate to -1 in the input data
    • Set R_CMT in [main]
  • It is an error to try to model the duration
    • Set rate to -2 in the input data
    • Set D_CMT in [main]