[Bioavailability of antiglaucoma drugs]

Area of Science:

• Ophthalmology and Pharmacology
• Drug Delivery Systems
• Corneal Physiology

Context:

• Antiglaucoma medications are typically administered as eye drops.
• The cornea and tear film present significant barriers to ocular drug penetration.
• High drug concentrations are often necessary to overcome these barriers.

Purpose:

• To review the literature on the bioavailability of common antiglaucoma drugs.
• To elucidate the factors affecting ocular drug penetration and systemic absorption.
• To highlight the challenges in achieving adequate drug concentrations in the eye.

Summary:

• Ocular drug bioavailability is primarily determined by the ability of drugs to permeate the cornea and resist clearance by the tear film.
• Systemic bioavailability of orally administered antiglaucoma drugs (e.g., beta-blockers) is well-documented, contrasting with the limited understanding of eye drop pharmacokinetics.
• This review examines literature on pilocarpine, beta-blockers, adrenergic agents (dipivalyl-epinephrine, apraclonidine, brimonidine), and carbonic anhydrase inhibitors (acetazolamide, dorzolamide).

Impact:

• Improved understanding of antiglaucoma drug delivery challenges.
• Informs the development of novel formulations for enhanced ocular bioavailability.
• Highlights the need for further research into individualized drug response in glaucoma treatment.