In simple words: Conjunctivitis, also known as pinkeye, is an inflammation or infection of the clear membrane (conjunctiva) that lines the eyelid and covers the white part of the eyeball.

Inflammation of the conjunctiva of the eye. The conjunctiva is the mucous membrane that lines the inner surface of the eyelids and the anterior part of the sclera.This condition is also known as pinkeye or redeye.

Example 1: A 3-year-old child presents with red, watery eyes, and a yellow discharge. The physician diagnoses bacterial conjunctivitis and prescribes antibiotic eye drops., A 25-year-old patient complains of itchy, red eyes and a history of seasonal allergies. The physician diagnoses allergic conjunctivitis and recommends antihistamine eye drops., A 50-year-old patient with a history of contact lens use presents with severe eye pain, redness, and blurred vision. The physician diagnoses contact lens-related keratitis (corneal inflammation) and refers the patient to an ophthalmologist.Note that keratitis itself would be coded differently, but the associated conjunctivitis could be coded H10.

Documentation should include laterality (which eye is affected), the type of conjunctivitis (if known), the severity of symptoms, any associated conditions, and the treatment plan.

** For accurate coding, it's important to differentiate H10 from other related eye conditions, such as keratitis and blepharitis, each having their specific ICD-10-CM codes.If the conjunctivitis is caused by an injury, use an external cause code following H10 to specify the cause of the injury.