How do subconjunctival medications access the eye?

Subconjunctival medications access the eye primarily through the process of absorption into the surrounding tissues, which can then lead to systemic circulation. When a medication is injected subconjunctivally, it lies beneath the conjunctiva, a membrane that covers the white part of the eye. From this location, the drug can diffuse into the nearby ocular structures and be absorbed into the bloodstream.

This method allows for localized delivery of medication with the potential for therapeutic effects in the eye, such as reducing inflammation or treating infections, while minimizing systemic side effects compared to other routes of administration.

Although options involving direct injection into the eye or diffusion through the tear film relate to ways medications can enter the eye, they do not accurately capture the primary pathway for subconjunctival injections, which is through absorption into systemic circulation. Similarly, evaporation from mucous membranes pertains to medication losses rather than access pathways to the eye. Understanding this process is crucial for the effective use of subconjunctival medications in ophthalmic practice.