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Istalol®

GoodRx

Timolol Maleate 0.5% · ophthalmic solution

Antiglaucoma

Indication
ISTALOL is a beta adrenergic blocker indicated for the treatment of elevated intraocular pressure in patients with ocular hypertension or open-angle glaucoma.
Contraindications
Bronchial asthma, a history of bronchial asthma, severe chronic obstructive pulmonary disease Sinus bradycardia, second or third degree atrioventricular block, overt cardiac failure, cardiogenic shock Hypersensitivity to any component of this product.
Available Forms
0.5% bottles, 5 mL, 10 mL, 2.5 mL, 7.5 mL
Mechanism of Action
Timolol maleate is a beta 1 and beta 2 (non-selective) adrenergic receptor blocking agent that does not have significant intrinsic sympathomimetic, direct myocardial depressant, or local anesthetic (membrane-stabilizing) activity. Beta-adrenergic receptor blockade reduces cardiac output in both healthy subjects and patients with heart disease. In patients with severe impairment of myocardial function, beta-adrenergic receptor blockade may inhibit the stimulatory effect of the sympathetic nervous system necessary to maintain adequate cardiac function.
Dosage
One drop of ISTALOL should be administered in the affected eye(s) once a day in the morning (AM). If more than one topical ophthalmic drug is being used, the drugs should be administered at least five minutes apart.
Warnings & Precautions
  • Potentiation of Respiratory Reactions Including Asthma: ISTALOL contains timolol maleate; and although administered topically, it can be absorbed systemically. Therefore, the same adverse reactions found with systemic administration of beta-adrenergic blocking agents may occur with topical administration.
  • Cardiac Failure: Sympathetic stimulation may be essential for support of the circulation in individuals with diminished myocardial contractility, and its inhibition of beta-adrenergic receptor blockade may precipitate more severe failure.
  • Obstructive Pulmonary Disease: Patients with chronic obstructive pulmonary disease (e.g., chronic bronchitis, emphysema) of mild or moderate severity, bronchospastic disease, or a history of bronchospastic disease [other than bronchial asthma or a history of bronchial asthma in which ISTALOL is contraindicated] should, in general, not receive beta-blocking agents, including ISTALOL .
  • Increased Reactivity to Allergens: While taking beta-blockers, patients with a history of atopy or a history of severe anaphylactic reactions to a variety of allergens may be more reactive to repeated accidental, diagnostic, or therapeutic challenge with such allergens.
  • Potentiation of Muscle Weakness: Beta-adrenergic blockade has been reported to potentiate muscle weakness consistent with certain myasthenic symptoms (e.g., diplopia, ptosis, and generalized weakness). Timolol has been reported rarely to increase muscle weakness in some patients with myasthenia gravis or myasthenic symptoms.
  • Masking of Hypoglycemic Symptoms in Patients with Diabetes Mellitus: Beta-adrenergic blocking agents should be administered with caution in patients subject to spontaneous hypoglycemia or to diabetic patients (especially those with labile diabetes) who are receiving insulin or oral hypoglycemic agents.
Common Side Effects
The most frequently reported adverse reactions have been burning and stinging upon instillation in 38% of patients treated with ISTALOL. Additional reactions reported with ISTALOL at a frequency of 4% to 10% include: blurred vision, cataract, conjunctival injection, headache, hypertension, infection, itching and decreased visual acuity.
Pregnancy & Lactation
Pregnancy: There are no adequate and well-controlled studies in pregnant women with timolol maleate to inform a drug-associated risk. Administration of oral timolol maleate to pregnant mice, rats and rabbits did not produce teratogenicity at clinically relevant systemic exposures .
Lactation: Timolol has been detected in human milk following oral and ophthalmic drug administration. The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for ISTALOL and any potential adverse effects on the breastfed child from ISTALOL.
Pediatric Use
The safety and effectiveness of ISTALOL in pediatric patients have not been established.