Evaluating Oral Drug Delivery Systems: Digestion Models

  • Ragna Berthelsen
  • Philip SasseneEmail author
  • Thomas Rades
  • Anette Müllertz
Part of the Advances in Delivery Science and Technology book series (ADST)


In order to assess drug release from a digestible drug delivery system (DDS), it is important to simulate the relevant digestion processes as well as the dissolution process. Compared to commonly used dissolution models, digestion models are typically more complex, as they incorporate the digestive enzymes. This also renders these models suitable for the evaluation of food effects on drugs and dosage forms.

In this chapter, the human digestion processes are briefly described, followed by a description of the most commonly used digestion models including the pH-stat controlled lipolysis models, the Dynamic Gastric Model (DGM) and TNO gastrointestinal model (TIM-1). The pH-stat controlled models are examples of relatively simple digestion models commonly used to evaluate the amount of drug solubilised in the aqueous phase during digestion of lipid based DDS (LbDDS), whereas the DGM and the TIM-1 represent two of the more complex dissolution and digestion models available. Emphasis will be on the models suitability to assess LbDDS and will therefore primarily involve lipid digestion.


Digestion In vitro GI tract Digestible drug delivery systems Lipid-based drug delivery systems Food effects pH-stat controlled lipolysis model DGM TIM-1 


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Copyright information

© Controlled Release Society 2016

Authors and Affiliations

  • Ragna Berthelsen
    • 1
  • Philip Sassene
    • 1
    Email author
  • Thomas Rades
    • 1
  • Anette Müllertz
    • 2
  1. 1.Department of PharmacyUniversity of CopenhagenCopenhagenDenmark
  2. 2.Bioneer:FARMA, Department of PharmacyUniversity of CopenhagenCopenhagenDenmark

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