# basic PK model for iv administration

[LONGITUDINAL]
input = {V, k}

PK:
depot(target=Ac)

EQUATION:
ddt_Ac = -k*Ac
Cc=Ac/V
setwd(dirname(parent.frame(2)$ofile)) library(ggplot2) #------------------------------------- adm <- list(time=3, amount=40) Cc <- list(name='Cc',time=seq(from=0, to=20, by=0.1)) p <- list(name=c('V','k'), value=c(10,0.4)) res <- simulx(model='pk1_model.txt', parameter=p, output=Cc, treatment=adm) plot1=ggplot(data=res$Cc, aes(x=time, y=Cc, group=id)) + geom_line(size=1)
print(plot1)

#### One compartment model for intravenous administration

The amount $$A_c$$ in the central compartment is solution of the ODE $$\ \ \dot{A_c}(t) = - k \, A_c(t)$$

The concentration $$C_c$$ in the central compartment is defined by $$\ \ C_c(t) = A_c(t)/V$$

• Define the dosage regimen in the tab iv: time of first dose, number of doses, interdose interval, infusion time, amount.

• select the PK parameters in the tab parameters:
• $$k$$, the elimination rate constant,
• $$V$$, the volume of the central compartment.

• define the outputs in the tab outputs :
• select the output to display: the amount $$A_c$$ or the concentration $$C_c$$,
• select the time range where the prediction is computed,
• select the number of time points of the grid where the prediction is computed.

• set some settings in the tab settings: line width, linear or semi-log scale.