Zero-order steady state infusion

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]

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mrgsolve: mrgsolve.github.io | metrum research group: metrumrg.com