Timolol. Hypotensive effect, used alone and in combination for treatment of increased intraocular pressure

In 43 persons with increased intraocular pressure (IOP) Timolol maleate eye drops (0.25% and 0.5%) were used as a single and combined treatment. A significant decrease in IOP was noticed in 34 persons (P less than 0.001) initially. No diminished effect of treatment was apparent after 9 weeks in 34 subjects or after 15 weeks in 23 subjects with Timolol alone. In nine persons with high IOP, Timolol had a significant (P less than 0.001) but insufficient lowering effect. Epinephrine (1%) and acetazolamide appeared to have an additive effect in these cases. No serious local or systemic adverse effects were discovered.