The Difference Between Vd and Vss

The Difference Between Vd and Vss

There are many terms used to represent volume of distribution, but two common ones are Vd and Vss. Vd is the apparent volume of distribution. It can be calculated using the following equation:


Vss is the apparent volume of distribution at steady state. Or, the sum of all volume terms in a multicompartment model. It can be calculated using the following equation:


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Nathan Teuscher

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Nathan Teuscher

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Dr. Nathan Teuscher is the Vice President of Pharmacometric Solutions at Certara. He is an expert in clinical pharmacology, pharmacometrics, pharmacokinetics and pharmacodynamics and was trained by David Smith at the University of Michigan. Dr. Teuscher has held leadership positions in biotechnology, pharmaceutical and contract research companies. In 2008 he established the Learn website to share his knowledge with the community. Prior to coming to Certara, he was the Founder and President of PK/PD Associates.