httk (version 1.4)

solve_1comp: Solve one compartment TK model

Description

This function solves for the amount or concentration of a chemical in plasma or blood for a one compartment model as a function of time based on the dose and dosing frequency.

Usage

solve_1comp(chem.cas=NULL,chem.name=NULL,times=NULL,parameters=NULL,daily.dose=1,
            dose=NULL,doses.per.day=NULL, days=10,tsteps = 4, suppress.messages=F,
            species='Human',output.units='uM',plots=F,initial.values=NULL,
            iv.dose=F,method="lsoda",rtol=1e-8,atol=1e-12,
            default.to.human=F,dosing.matrix=NULL,recalc.elimination=F,...)

Arguments

chem.name

Either the chemical name, CAS number, or the parameters must be specified.

chem.cas

Either the chemical name, CAS number, or the parameters must be specified.

times

Optional time sequence for specified number of days.

parameters

Chemical parameters from parameterize_1comp function, overrides chem.name and chem.cas.

days

Length of the simulation.

tsteps

The number time steps per hour.

daily.dose

Total daily dose, mg/kg BW.

dose

Amount of a single dose, mg/kg BW. Overwrites daily.dose.

doses.per.day

Number of doses per day.

species

Species desired (either "Rat", "Rabbit", "Dog", or default "Human").

iv.dose

Simulates a single i.v. dose if true.

output.units

Desired units (either "mg/L", "mg", "umol", or default "uM").

initial.values

Vector containing the initial concentrations or amounts of the chemical in specified tissues with units corresponding to output.units. Defaults are zero.

suppress.messages

Whether or not the output message is suppressed.

plots

Plots all outputs if true.

method

Method used by integrator (deSolve).

rtol

Argument passed to integrator (deSolve).

atol

Argument passed to integrator (deSolve).

default.to.human

Substitutes missing rat values with human values if true.

dosing.matrix

Vector of dosing times or a matrix consisting of two columns or rows named "dose" and "time" containing the time and amount, in mg/kg BW, of each dose.

recalc.elimination

Whether or not to recalculate the elimination rate.

...

Additional arguments passed to the integrator.

Value

• A matrix with a column for time(in days) and a column for the compartment and the area under the curve (concentration only).

Details

Note that the model parameters have units of hours while the model output is in days. Default value of NULL for doses.per.day solves for a single dose. When species is specified as rabbit, dog, or mouse, the function uses the appropriate physiological data(volumes and flows) but substitues human fraction unbound, partition coefficients, and intrinsic hepatic clearance. AUC is area under plasma concentration curve.

Examples

solve_1comp(chem.name='Bisphenol-A')
solve_1comp(chem.name='Bisphenol-A',doses.per.day=3,tsteps=50,days=20)