Effects of long-term treatment with timolol on lacrimal gland function

Thirty-two patients with raised intraocular pressure were treated for 1 year with topical timolol 0.5% twice daily. There was satisfactory pressure reduction on this drug alone in 25 patients. The tear flow (modified Schirmer I test) was measured, and the tear lysozyme concentration was assayed before, and at 3, 6, and 12 months after beginning treatment. No subjective symptoms occurred and no side effects were recorded. The tear flow and tear lysozyme concentration were not significantly reduced.