Use Volume Of Distribution when you need to compute the apparent volume of distribution from a dose and plasma concentration. Enter Dose and Plasma concentration using the definitions and units below so the result can be reproduced.

Dose

A finite measured or assumed value, expressed in mg.

Plasma concentration

A finite measured or assumed value, expressed in mg/L.

The published tool contract uses this rule: Compute the apparent volume of distribution from a dose and plasma concentration.

Volume of distribution

The calculated volume of distribution in L.

A ratio or percentage can conceal the scale of its numerator and denominator and becomes sensitive to measurement error when the denominator is small. It is informational and cannot diagnose a condition, select treatment, or replace professional interpretation of the original measurements.

Retain the original Dose and Plasma concentration values and their units alongside the result. Apparent Vd is useful when you instead need to estimate volume of distribution as the systemically available dose (administered dose times bioavailability) divided by plasma concentration. Plasma Volume mL provides another view by helping you compute the plasma volume as blood volume times one minus the hematocrit fraction.

• Apparent Vd

  Estimate volume of distribution as the systemically available dose (administered dose times bioavailability) divided by plasma concentration.

• Plasma Volume mL

  Compute the plasma volume as blood volume times one minus the hematocrit fraction.

• RDW-CV Percent

  Compute red cell distribution width CV from RBC volume standard deviation and MCV.