A general approach to the selection of the maintenance dose (Dm) required to give a desired steady‐state concentration of drug based on a single determination of concentration after a test dose (C*) is extended to drugs with two‐compartment pharmacokinetic characteristics. Using the equation developed, the value of the proportionality factor relating 1/Dm to C* was found to be within 3.2% of the value calculated from a published nomogram for lithium. The inherent error is shown to be a function of the value of the hybrid rate constants α and β, as well as the value of an intercompartmental transfer rate constant, k21, in an individual.
Bibliographical noteFunding Information:
The authors thank Dr. E. M. Hawes for helpful discussions and Mr. K. Hall for mass spectral analysis. The postdoctoral award from Sas- katchewan Health Research Board to G. McKay is gratefully acknowledged.
- Concentration, steady‐state—maintenance dose, prediction by single determination of concentration, two‐compartment pharmacokinetics, lithium
- Dose, maintenance—steady‐state concentration, prediction by single determination of concentration, two‐compartment pharmacokinetics, lithium
- Pharmacokinetics—two‐compartment, maintenance dose for steady‐state concentration, prediction by single determination of concentration, lithium