Current and Developing Therapeutics for Dry Eye Disease: Targeting Ion Channels.

Dry eye disease (DED) is an ocular surface disorder characterized by tear film instability, inflammation, epithelial damage, and neurosensory abnormalities. Due to its multifactorial etiology and pathophysiology, conventional therapies that focus on lubrication and immunosuppression often fall short in addressing the neuropathic component of ocular pain experienced by a growing subset of patients. Recent developments in sensory neuroscience have highlighted the pivotal role of ion channels in mediating ocular surface homeostasis, pain signaling, and inflammation. This review examines the role of the following major ion channel families in the pathophysiology of DED and neuropathic ocular pain: transient receptor potential (TRP) channels, voltage-gated sodium (Nav) channels, and purinergic P2X receptors. The review details their anatomical distribution, molecular function, and responses to environmental stimuli such as heat, cold, osmolarity, and injury. Current treatments, such as artificial tears, anti-inflammatory drops, and systemic neuromodulators, are also reviewed in relation to their effects on ion channel modulation. Additionally, emerging therapies that directly target sensory transduction pathways are introduced. This review highlights the therapeutic potential of ion channel modulation in personalizing treatment for patients with ocular surface pain, particularly those with neuropathic features unresponsive to standard care.