Efficacy of oxymetazoline eye drops in non-infectious conjunctivitis, the most common cause of acute red eyes.

Oxymetazoline (OMZ) is an alpha-adrenergic agonist which causes potent vasoconstriction in various tissues. Thus, its effects on red eye conjunctivitis induced by histamine and arachidonic acid were tested in rabbit eyes. It was found that a brief conjunctivitis induced by 0.01% of histamine can be eliminated effectively by 0.001, 0.004, and 0.016% of OMZ. The long lasting conjunctivitis induced by 0.3% arachidonic acid can also be markedly reduced by 0.004, 0.008, and 0.016% of OMZ. These results indicate that OMZ is a potent, long acting decongestant for conjunctival red eye syndrome.