Drug delivery systems for enhanced ocular absorption

Muhammad Abdulrazik, Francine Behar-Cohen, Simon Benita

Research output: Chapter in Book/Report/Conference proceedingChapterpeer-review

1 Scopus citations

Abstract

To date, nearly all ocular therapeutics have been administered to the eye as simple aqueous solution eyedrops by instillation to the lower conjunctival sac. The main drawbacks of aqueous eyedrops are their inability to deliver lipophilic and insoluble molecules, their low retention time, and their limited ability to resist the washout effect of blinking and tears turnover. The expected 10% to 20% fraction of the applied topical dose that escapes the immediate washout by blinking and tearing is then challenged by tear fluid proteins and enzymes binding and metabolism, ocular permeation barriers, phagocytic activity and partial diversion to adjacent tissues, and systemic circulation. Thus, more drug elimination occurs before it reaches the target tissue. Therefore, it is estimated that only 1% or less of the administered dose can penetrate the ocular surface [1,2]. Moreover, when targeting a remote target tissue like the retina, the fraction of the administered dose that reaches the action site will be much less due to further anatomical barriers, aqueous humor turnover, intraocular metabolic activity, binding to intraocular pigmented tissues, and phagocytosis by cell line other than the targeted tissue cells.

Original languageEnglish
Title of host publicationEnhancement in Drug Delivery
PublisherCRC Press
Pages490-525
Number of pages36
ISBN (Electronic)9781420004816
ISBN (Print)9780849332036
StatePublished - 1 Jan 2006

Bibliographical note

Publisher Copyright:
© 2011 by Taylor & Francis Group, LLC.

Fingerprint

Dive into the research topics of 'Drug delivery systems for enhanced ocular absorption'. Together they form a unique fingerprint.

Cite this