Multi-compartment PK Parameter Conversion Calculator

This calculator converts clearance (CL) and volume (V) parameters for 2- and 3-compartment mammillary PK models to corresponding micro- and macro-rate constants. Enter CL, VC, Q1, V P1 (and Q2, VP2 for three-compartment models). Derived half-lives and VSS are also output.

Multi-compartment PK Parameter Conversion Calculator

This calculator converts clearance (CL) and volume (V) parameters for 2- and 3-compartment mammillary PK models to corresponding micro- and macro-rate constants. Derived half-lives and steady-state volume of distribution (VSS) are also output.

Optional parameter overrides

Optional inputs list units as volume or inverse time.

Note: Calculations follow clearance and volume-based two- and three-compartment model relationships. Optional overrides replace the computed values when provided. Validate outputs against your model specification and assumptions before use.

About the models and equations

Diagrammatic representation of the three-compartment model.

Calculations are based on clearance and volume parameterizations of the classical 2- and 3-compartment mamillar models.

VSS = VC + VP1 (+ VP2)

k10 = CL / VC

k12 = Q1 / VC

k21 = Q1 / VP1

k13 = Q2 / VC (three-compartment)

k31 = Q2 / VP2 (three-compartment)

α, β (two-compartment) from the quadratic roots of the CL/V-based system

α, β, γ (three-compartment) from the cubic roots of the CL/V-based system

t1/2 = ln(2) / rate

Important: These equations match the CL/V-based models in the PKconverter package. Always validate with your team’s modeling conventions and assumptions.

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