The episclera is a thin vascular membrane between the conjunctiva and the sclera.
Episcleritis occurs in young adults, more commonly among women. It is usually idiopathic; it can be associated with connective tissue diseases and rarely with serious systemic diseases (present in about 15% of patients). (See also Overview of Conjunctival and Scleral Disorders.)
Mild irritation occurs. Additionally, a bright red patch is present just under the bulbar conjunctiva (simple episcleritis). A hyperemic, edematous, raised nodule (nodular episcleritis) may also be present. The palpebral conjunctiva is normal.
Episcleritis is distinguished from conjunctivitis by hyperemia localized to a limited area of the globe, much less lacrimation and no discharge. It is distinguished from scleritis by lack of photophobia and lack of severe pain.
The condition is self-limited. If the review of systems does not suggest an underlying cause, then a diagnostic assessment for systemic disorders is not routinely warranted.
A topical corticosteroid (eg, prednisolone acetate, 1% drops 4 times a day for 7 days, gradually reduced over 3 weeks) or an oral nonsteroidal anti-inflammatory drug usually shortens the attack; corticosteroids are usually prescribed by an ophthalmologist. Topical vasoconstrictors (eg, tetrahydrozoline, brimonidine tartrate 0.025%) to improve appearance are optional; however, regular use can worsen erythema due to rebound.