Dry eye is a medical problem of epidemic proportions, especially among the elderly in developed countries. The treatment of dry eye is still largely inadequate because there is no way of permanently restoring normal tear function and secretion at present. At present, virtually all therapeutic regimens include tear supplements; however, their main drawbacks are the need for frequent instillation, inadequate ocular surface protection and limited mode of action, focusing on rewetting only. OBJECTIVE: A new gellable lubricant eye drop (Systane lubricant eye drops, Alcon) has been designed using the novel concept of a pH-sensitive hydroxypropyl-guar component that prevents surface desiccation, reduces friction and acts as a mucomimetic. The purpose of this review is to consider this topical therapy and its properties. METHODS: Currently published data on Systane is reviewed, putting an accent on its novel multiple modality of action. RESULTS/CONCLUSION: By being pH sensitive, Systane adapts its viscosity to the ocular surface pH, which tends to be higher in dry eye. It becomes more viscous when the eye is drier, thus, providing better ocular surface protection. In addition, its characteristics reduce ocular surface friction, which is another factor that exacerbates dry eye symptoms. Data published so far show that it is also well tolerated by the patient, thus, significantly reducing dry eye symptoms and improving the patient's quality of life. By implementing this novel approach, Systane has contributed significantly to dry eye treatment. |