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Periocular routes for retinal drug delivery
Swita Raghava1, Makena Hammond, Uday B Kompella
1University of Nebraska Medical Centre, Department of Pharmaceutical Sciences, Omaha, NE 68198-5840, USA.
Expert Opinion on Drug Delivery
|November 22, 2005
Summary
Periocular drug delivery offers a promising alternative for treating the retina, bypassing limitations of topical and systemic methods. This approach enhances drug delivery, especially for chronic conditions, by utilizing scleral permeability.
Area of Science:
- Ophthalmology
- Pharmacology
- Drug Delivery Systems
Background:
- Delivering therapeutic drug concentrations to the retina, particularly for chronic conditions, remains a significant challenge in ophthalmology.
- Topical and systemic drug administration routes are often inefficient or inadequate for achieving effective retinal drug levels.
- Intravitreal injections, while effective, carry risks of serious side effects like cataracts and retinal detachment with repeated use.
Purpose of the Study:
- To review and evaluate periocular routes as a potentially superior alternative for retinal drug delivery.
- To discuss the anatomical, pharmacokinetic, and safety aspects of various periocular drug administration methods.
- To highlight the potential of periocular routes for sustained-release drug delivery to the retina.
Main Methods:
- Review of existing scientific literature on periocular drug delivery techniques.
- Analysis of anatomical locations, pharmacokinetic profiles, and safety data for subconjunctival, sub-tenon, retrobulbar, peribulbar, and posterior juxtascleral routes.
- Discussion of the mechanisms by which periocular routes facilitate drug penetration through the sclera to the retina.
Main Results:
- Periocular routes, including subconjunctival, sub-tenon, and juxtascleral approaches, demonstrate potential for enhanced retinal drug delivery.
- These routes leverage scleral permeability and are suitable for sustained-release formulations of potent drugs.
- Periocular administration offers advantages over topical and systemic routes for achieving therapeutic retinal drug concentrations.
Conclusions:
- Periocular drug delivery represents a promising strategy to overcome current limitations in retinal pharmacotherapy.
- Further innovations in absorption enhancers, drug delivery systems, and administration devices are expected to optimize periocular retinal drug delivery.
- Continued research into periocular routes holds significant potential for improving the management of retinal diseases.
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