[How I treat...a red eye].

Before any initiation of treatment for a red eye, an accurate differential diagnosis must absolutely be done, as considered in a previous article. Red eye can result from benign diseases, but also from serious pathologies which shouldn't be neglected, as they require a rapid ophtalmologist management. This is the case for keratitis, uveitis, acute glaucoma attack, or endophtalmitis. Treatment of red eye will just be symptomatic in benign diseases but, in contrast, will absolutely need an etiological diagnosis and therapeutic approach in more serious cases. Generally speaking, topical steroids should never be prescribed in doubt of infectious keratitis. Moreover, local anaesthetics, because of their toxicity for the cornea, should not be prescribed under any circumstances.