Dry eye: why artificial tears are not always the answer.

Dry eye disease (DED) is a multifactorial disease that manifests in patients with a variety of symptoms and signs such as ocular pain, visual issues, rapid tear evaporation and/or decreased tear production. It is a global health problem and is the leading cause of optometry and ophthalmology clinic visits. The mainstay therapy for DED is artificial tears (ATs), which mimics tears and improves tear stability and properties. ATs have been found to improve symptoms and signs of disease in all DED subtypes, including aqueous deficient DED and evaporative DED. However, given the heterogeneity of DED, it is not surprising that ATs are not effective in all patients. When AT fails to relieve symptoms and/or signs of DED, it is critical to identify the underlying contributors to disease and escalate therapy appropriately. This includes underlying systemic diseases, meibomian gland dysfunction, anatomical abnormalities and neuropathic dysfunction. Thus, this review will discuss the benefits and limitations of ATs and review conditions when escalation of therapy should be considered in DED.