The PK: block can be included into the [LONGITUDINAL] section and can serve two main functions:

  1. It is used to provide a link between the administration information in the data set and the model.
  2. It is for the use of macros that are dedicated to the description of PK models. These macros allow the user to have an intuitive and compact representation of the most common PK models used in pharmacometrics.

Inputs and outputs

The PK: block has no inputs or outputs. It rather declares that a set of macros that define the administration and/or a PK model.


  1. Before an administration macro can be used the corresponding compartments must be defined first using a compartment macro
  2. PK macros cannot be included into an arithmetic expression
  3. PK macros cannot be enclosed within a conditional statement
  4. Macros can be used along ODE equations
  5. The PK: block must be in the [LONGITUDINAL] section

PK macros by function

The following two links provide overview tables: