Calculation of the Rate of Absorption of Exogenous Creatinine

Summary and Conclusions

For an inert substance in diffusion equilibrium, the rate of absorption at any time is shown to be equal to the rate of excretion plus the product of the volume of distribution and the rate of change in the concentration of the substance in the plasma. Two solutions of this equation are described and are applied to the absorption of creatinine in 3 human beings.