NONMEM Users Network Archive

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Re: Steady state model

From: Bill Gillespie <billgillespie>
Date: Fri, 7 Aug 2009 07:43:55 -0400

Hi Sherwin,

As Nick said, Alison would be the best source fro details, but I can
give you the basic idea of what's done. For the constant rate input
case, the solution is obtained as Nick described. In the case of
multiple dosing with equal doses and dosing intervals, it is a root-
finding problem that iteratively seeks a vector of values for the
initial amounts in the compartments. The solution is the set of values
such that the initial and final (end of dosing interval) values are
equal for all compartments.


On Aug 5, 2009, at 2:44 PM, Sherwin K Sy wrote:

> Dear NONMEM users,
> I'm wondering what equation or ODE is used in NONMEM when the steady
> state is set (i.e. SS = 1). Is it the case that the initial
> parameter for the compartment is set to a different value? If so,
> how does NONMEM set this value?
> I would appreciate if anyone can provide me with a reference or
> point me to where I can find this information, including the type of
> equation used for extravascular, iv bolus and iv infusion models.
> Thanks,
> Sherwin
Received on Fri Aug 07 2009 - 07:43:55 EDT

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