Timolol maleate ophthalmic solution is available in concentrations of 0.25 and 0.5 percent. The usual starting dose is one drop of 0.25 percent timolol maleate ophthalmic solution in the affected eye(s) twice a day. If the clinical response is not adequate, the dosage may be changed to one drop of 0.5 percent solution in the affected eye(s) twice a day.
Since in some patients the pressure-lowering response to timolol may require a few weeks to stabilize, evaluation should include a determination of intraocular pressure after approximately 4 weeks of treatment with timolol.
If the intraocular pressure is maintained at satisfactory levels, the dosage schedule may be changed to one drop once a day in the affected eye(s). Because of diurnal variations in intraocular pressure, satisfactory response to the once-a-day dose is best determined by measuring the intraocular pressure at different times during the day.
Dosages above one drop of 0.5 percent timolol maleate ophthalmic solution twice a day generally have not been shown to produce further reduction in intraocular pressure. If the patient's intraocular pressure is still not at a satisfactory level on this regimen, concomitant therapy with other agent(s) for lowering intraocular pressure can be instituted.
The concomitant use of two topical beta-adrenergic blocking agents is not recommended. (See PRECAUTIONS, Drug Interactions, Beta-adrenergic blocking agents.)