Istalol is a once-daily beta-blocking agent for the treatment of elevated intraocular pressure for your patients with ocular hypertension or open-angle glaucoma1Istalol, formulated with potassium sorbate, has been shown to have 3 times the ocular bioavailability2 and 75% less systemic absorption3 vs. other timolol solutions.  

24-hour control with minimal diurnal fluctuation and convenient morning dosing, Istalol is an excellent choice for monotherapy, or as an adjunct to a prostaglandin1

Clinical Study

In a well controlled, double-masked, parallel study of 332 patients with untreated intraocular pressures of 22 mm Hg or greater, Istalol administered once daily (AM) was equivalent to timolol maleate oph­thalmic solution 0.5% administered twice daily4. In both groups, mean intraocular pressure decreased from 25 mm Hg at baseline to 18 mm Hg at peak and 19 mm Hg at trough4. Istalol has been shown to be safe, effective, and generally well tolerated in multiple studies with only 3% of patients discontinuing use due to adverse events over a 12 month period.

Ocular Hypertension Treatment Study (OHTS)

There are millions of people in the United States who have increased pressure in their eyes (intraocular pressure) without glaucoma. One of the largest studies of ocular hypertension, the Ocular Hypertension Treatment Study (OHTS), proved that topical medication reduces the incidence of glaucoma and supports offering eyedrop treatment to ocular hypertensive people who are at moderate to high risk for developing glaucoma.

Contraindications, Warnings, Adverse Reactions

Istalol is contraindicated in patients with (1) bronchial asthma; (2) a history of bronchial asthma; (3) severe chronic obstructive pulmonary disease (see WARNINGS/full Prescribing Information(92.2 KB, PDF)); (4) sinus bradycardia; (5) second or third degree atrioventricular block; (6) overt cardiac failure (see WARNINGS/full Prescribing Information(92.2 KB, PDF)); (7) cardiogenic shock; or (8) hypersensitivity to any component of this product.

As with many topically applied ophthalmic drugs, this drug is absorbed systemically. The same adverse reactions found with systemic administration of beta-adrenergic blocking agents may occur with topical administration. For example, severe respiratory reactions and cardiac reactions, including death due to bronchospasm in patients with asthma, and rarely death in association with cardiac failure, have been reported following systemic or ophthalmic administration of timolol maleate (see CONTRAINDICATIONS/full Prescribing Information(92.2 KB, PDF)).1

The most frequently reported adverse experiences have been burning and stinging upon instillation in 38% of patients treated with Istalol. Additional events reported with Istalol at a frequency of 4 to 10% include: blurred vision, cataract, conjunctival infection, itching and decreased visual acuity.

Please click here(92.2 KB, PDF) to view Istalol full Prescribing Information.


1Istalol [Package Insert]. ISTA Pharmaceuticals, Inc., Irvine, CA.
2 Higashiyama M, Inada K, Ohtori A, et al. Improvement of the ocular bioavailability of timolol by sorbic acid. Int J Pharm. 2004;272:91-98.
3 Mundorf TK, Ogawa T, Inui N, et al. Timolol LA: a double-masked, active-controlled, randomized, crossover, comfort, ocular safety, and systemic bioavailability study in healthy volunteers. Curr Med Res Opin. 2005;21:369-373.
4 Mundorf TK, Ogawa T, Naka H, et al. A 12-month, multicenter, randomized, double-masked, parallel-group comparison fo timolol-LA once daily and timolol maleate ophthalmic solution twice daily in the treatment of adults with glaucoma or ocular hypertension. Clin Ther. 2004;26:541-551.