Oily (Lipophilic) Solutions and Suspensions

  • Susan W. Larsen
  • Mette A. Thing
  • Claus Larsen
Part of the Advances in Delivery Science and Technology book series (ADST)


Formulation of drugs in the form of lipophilic solutions or suspensions may lead to a considerable prolongation of drug action following parenteral administration. The in vivo performance of such oil depot injectables are influenced by three major parameters, i.e., the rate of drug release from the oil vehicle, the degree of drug load, and the syringeability. Thus, the aim of this chapter is mainly to give a brief overview over various means to manipulate in vitro characteristics including (1) vehicle viscosity, (2) drug solubility in oil vehicles, and (3) drug partitioning between oil and aqueous buffer. Furthermore, the utility of in vitro release models in the design of lipophilic drug formulations and for quality control purposes is discussed.


Drug Release Drug Load Ricinoleic Acid Isopropyl Myristate Mixture Viscosity 
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Copyright information

© Controlled Release Society 2012

Authors and Affiliations

  • Susan W. Larsen
    • 1
  • Mette A. Thing
    • 1
  • Claus Larsen
    • 1
  1. 1.Department of Pharmaceutics and Analytical Chemistry, Faculty of Pharmaceutical SciencesUniversity of CopenhagenCopenhagenDenmark

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