How is conjunctivitis typically diagnosed?

Conjunctivitis is typically diagnosed through clinical assessment, which involves a healthcare provider examining the patient's eyes and reviewing their symptoms. The examination includes checking for redness, discharge, swelling, and any other signs that indicate inflammation of the conjunctiva. The provider may inquire about the duration of symptoms, any associated discomfort, and potential exposure to irritants or infectious agents.

While laboratory tests can sometimes be used to help identify the specific cause of conjunctivitis—such as differentiating between viral and bacterial infections—they are not routinely necessary for a straightforward diagnosis in typical cases. Imaging studies are generally not applicable to conjunctivitis because the condition primarily affects the surface layers of the eye rather than deeper structures. Patient history is an important component of the assessment but is not sufficient alone to diagnose conjunctivitis without a clinical evaluation. Thus, the combination of a thorough examination and symptom assessment leads to the most definitive diagnosis.