Clinical features:
(1) A topical ophthalmic medication is started to treat conjunctivitis or other condition.
(2) Ocular symptoms become worse and the person increases the use of the medication or may start another.
(3) Examination of the conjunctiva may show areas of erythema and/or necrosis, which are often worse in the inferior half of the bulbar conjunctiva since the ocular medication tends to have a higher concentration there.
(4) Examination of the cornea after fluorescein staining may show diffuse staining.
(5) Clinical improvement occurs after discontinuation of the causative medication or switch to a solution with minimal additives.
If multiple medications are used then each may be readded over time with assessment of tolerability. This process may be challenging if multiple ocular medications have been used and one or more are considered essential.
Mechanism:
(1) direct irritation caused by the active drug, often an antibiotic
(2) direct irritation secondary to a preservative or other additive
(3) allergic reaction
Differential diagnosis:
(1) infectious conjunctivitis
(2) tear insufficiency
(3) contamination of ophthalmic solution
