Interleukin-1β tear concentration in glaucomatous and ocular hypertensive patients treated with preservative-free nonselective beta-blockers

The use of preservatives in timolol 0.5% eyedrops leads to tear film instability and ocular surface inflammatory changes documented by a reduction of breakup time and an increase of IL-1β tear concentrations. Preservative-free beta-blockers are preferable for long-term hypotensive therapy to prevent ocular surface inflammation.