EFFECT OF TOPICALLY APPLIED OXYMETAZOLINE ON TEAR VOLUME AND TEAR FLOW IN HUMANS

Vasoconstrictive, alpha-sympathicomimetic eye drops are ophthalmic drugs that are extensively used. However, patients often complain of typical dry eye symptoms, especially after long-lasting application of such eye drops. In the present study, the effect of sympathicomimetic eye drops (0.026% oxymetazoline) on the tear volume and tear flow of 38 healthy individuals was determined quantitatively by means of objective fluorophotometry. Both tear volume and tear flow were found to be significantly (P < 0.001) decreased up to 6 h after instillation, reaching a minimum 90 min after application (tear volume: -63%; tear flow: -71%). Thus, alpha-sympathicomimetic eye drops containing 0.026% oxymetazoline lead to a marked and protracted decrease in tear volume and tear flow. After frequent or long-lasting application, this fact may be responsible for severe dry eye conditions.