What is considered the normal pH of the tear film?

The normal pH of the tear film typically ranges around 7.45, which aligns with the physiological pH of human blood and extracellular fluid. This slightly alkaline pH is crucial for maintaining comfort in the eye and optimizing the performance of various enzymes and proteins in the tear film. The tear film's composition, which includes water, salts, proteins, and lipids, plays a vital role in protecting the ocular surface and providing optimal conditions for visual function. A pH of 7.45 supports proper tear viscosity and stability, enhancing its protective and lubrication functions. Maintaining this pH is essential for overall ocular health, as deviations can lead to discomfort, dryness, or potential irritation of the corneal and conjunctival tissues.