Pharmaceutical Research

, Volume 23, Issue 2, pp 243–255 | Cite as

Advances in the Use of Tocols as Drug Delivery Vehicles

  • Panayiotis P. Constantinides
  • Jihong Han
  • Stanley S. Davis
Expert Review

Abstract

There has been increasing interest in recent years in the drug delivery applications of tocols and their derivatives. Their biocompatibility and potential to deliver both poorly soluble and water-soluble drugs make tocols attractive as drug delivery vehicles. This review article will focus primarily on topical, oral, and parenteral drug administration using tocols, although other routes of delivery such as pulmonary and nasal will also be discussed. After an overview of the tocol structures, physicochemical properties with emphasis on their solvent properties, functions, and metabolism, specific case studies will be discussed where tocols have been successfully used in topical, oral, and parenteral drug formulations and marketed drug products. Case studies will be extended to those where tocol-based formulations were administered pulmonarily and nasally. As more clinical data and marketed drug products emerge, the utility and therapeutic value of tocols will certainly increase.

Key Words

bioavailability enhancement tocol chemistry drug solubilization oral parenteral drug delivery P-glycoprotein inhibition tocols topical 

Notes

Acknowledgments

We would like to thank Professor Simon Benita of Hebrew University, School of Pharmacy, Jerusalem, Israel, and Dr. Lawrence Yu of the Food and Drug Administration Agency, CDER, Rockville, MD, for permission to include some of their published work in this review article. We are grateful to Dr. Andreas M. Papas of Yasoo Health Inc., Johnson City, TN, for providing the structures of tocopherols and tocotrienols and useful discussions on the function and metabolism of these molecules.

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Copyright information

© Springer Science + Business Media, Inc. 2006

Authors and Affiliations

  • Panayiotis P. Constantinides
    • 1
  • Jihong Han
    • 2
  • Stanley S. Davis
    • 3
  1. 1.Biopharmaceutical & Drug Delivery Consulting, LLCGurneeUSA
  2. 2.Centre for Paediatric Pharmacy Research, School of PharmacyUniversity of LondonLondonUK
  3. 3.School of PharmacyUniversity of NottinghamNottinghamUK

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