Levobunolol

INDICATIONS AND USAGE Levobunolol hydrochloride ophthalmic solution has been shown to be effective in lowering intraocular pressure and may be used in patients with chronic open-angle glaucoma or ocular hypertension.

DOSAGE AND ADMINISTRATION The recommended starting dose is one to two drops of levobunolol hydrochloride ophthalmic solution, 0.5% in the affected eye(s) once a day. In patients with more severe or uncontrolled glaucoma, levobunolol hydrochloride ophthalmic solution, 0.5% can be administered twice a day. As with any new medication, careful monitoring of patients is advised. Dosages above one drop of levobunolol hydrochloride ophthalmic solution, 0.5% twice a day are not generally more effective. If the patient's IOP is not at a satisfactory level on this regimen, concomitant therapy with other ophthalmic IOP-lowering agents can be instituted. Patients should not typically use two or more topical ophthalmic beta-adrenergic blocking agents simultaneously.

WARNINGS As with other topically applied ophthalmic drugs, levobunolol hydrochloride ophthalmic solution may be 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 with topical application of beta-adrenergic blocking agents (see CONTRAINDICATIONS ). Additionally, ophthalmic beta-blockers may impair compensatory tachycardia and increase risk of hypotension. Cardiac Failure Sympathetic stimulation may be essential for support of the circulation in individuals with diminished myocardial contractility, and its inhibition by beta-adrenergic receptor blockade may precipitate more severe failure. In Patients Without a History of Cardiac Failure Continued depression of the myocardium with beta-blocking agents over a period of time can, in some cases, lead to cardiac failure. At the first sign or symptom of cardiac failure, levobunolol hydrochloride ophthalmic solution should be discontinued (see CONTRAINDICATIONS ). Potentiation of Vascular Insufficiency Levobunolol hydrochloride ophthalmic solution may potentiate syndromes associated with vascular insufficiency (i.e. Raynaud’s phenomenon), and therefore, should be used with caution in these patients. 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 LEVOBUNOLOL HYDROCHLORIDE OPHTHALMIC SOLUTION IS CONTRAINDICATED, SEE CONTRAINDICATIONS ), SHOULD IN GENERAL NOT RECEIVE BETA BLOCKERS, INCLUDING LEVOBUNOLOL HYDROCHLORIDE OPHTHALMIC SOLUTION. However, if levobunolol hydrochloride ophthalmic solution is deemed necessary in such patients, then it should be administered cautiously since it may block bronchodilation produced by endogenous and exogenous catecholamine stimulation of beta 2 receptors. Major Surgery The necessity or desirability of withdrawal of beta-adrenergic blocking agents prior to major surgery is controversial. Beta-adrenergic receptor blockade impairs the ability of the heart to respond to beta-adrenergically mediated reflex stimuli. This may augment the risk of general anesthesia in surgical procedures. Some patients receiving beta-adrenergic receptor blocking agents have been subject to protracted severe hypotension during anesthesia. Difficulty in restarting and maintaining the heartbeat has also been reported. For these reasons, in patients undergoing elective surgery, gradual withdrawal of beta-adrenergic blocking agents may be appropriate. If necessary during surgery, the effects of beta-adrenergic blocking agents may be reversed by sufficient doses of such agonists as isoproterenol, dopamine, dobutamine or levarterenol (see OVERDOSAGE ). 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. Beta-adrenergic blocking agents may mask the signs and symptoms of acute hypoglycemia. Thyrotoxicosis Beta-adrenergic blocking agents may mask certain clinical signs (e.g., tachycardia) of hyperthyroidism. Patients suspected of developing thyrotoxicosis should be managed carefully to avoid abrupt withdrawal of beta-adrenergic blocking agents which might precipitate a thyroid storm. Choroidal Detachment Choroidal detachment after filtration procedures has been reported with the administration of aqueous suppressant therapy. These products contain sodium metabisulfite, a sulfite that may cause allergic-type reactions including anaphylactic symptoms and life-threatening or less severe asthmatic episodes in certain susceptible people. The overall prevalence of sulfite sensitivity in the general population is unknown and probably low. Sulfite sensitivity is seen more frequently in asthmatic than in nonasthmatic people.

CONTRAINDICATIONS Levobunolol hydrochloride ophthalmic solution is contraindicated in those individuals with bronchial asthma, or with a history of bronchial asthma, or severe chronic obstructive pulmonary disease (see WARNINGS ); sinus bradycardia; second and third degree atrioventricular block; overt cardiac failure (see WARNINGS ); cardiogenic shock; or hypersensitivity to any component of these products.

ADVERSE REACTIONS In clinical trials the use of levobunolol hydrochloride ophthalmic solution has been associated with transient ocular burning and stinging in up to 1 in 3 patients, and with blepharoconjunctivitis in up to 1 in 20 patients. Decreases in heart rate and blood pressure have been reported (see CONTRAINDICATIONS and WARNINGS ). The following adverse reactions have been reported rarely with the use of levobunolol hydrochloride ophthalmic solution: iridocyclitis, headache, transient ataxia, dizziness, lethargy, urticaria, and pruritus. Decreased corneal sensitivity has been noted in a small number of patients. Although levobunolol has minimal membrane-stabilizing activity, there remains a possibility of decreased corneal sensitivity after prolonged use. The following additional adverse reactions have been reported either with levobunolol hydrochloride ophthalmic solution or ophthalmic use of other beta-adrenergic receptor blocking agents: BODY AS A WHOLE: Headache, asthenia, chest pain. CARDIOVASCULAR: Bradycardia, arrhythmia, hypotension, syncope, heart block, cerebral vascular accident, cerebral ischemia, congestive heart failure, palpitation, cardiac arrest. DIGESTIVE: Nausea, diarrhea. PSYCHIATRIC: Depression, confusion, increase in signs and symptoms of myasthenia gravis, paresthesia. SKIN: Hypersensitivity, including localized and generalized rash, alopecia, Stevens-Johnson Syndrome. RESPIRATORY: Bronchospasm (predominantly in patients with pre-existing bronchospastic disease), respiratory failure, dyspnea, nasal congestion. UROGENITAL: Impotence. ENDOCRINE: Masked symptoms of hypoglycemia in insulin-dependent diabetics (see WARNINGS ). SPECIAL SENSES: Signs and symptoms of keratitis or eye allergy, blepharoptosis, visual disturbances including refractive changes (due to withdrawal of miotic therapy in some cases), diplopia, ptosis, and foreign body sensation in eye. Other reactions associated with the oral use of non-selective adrenergic receptor blocking agents should be considered potential effects with ophthalmic use of these agents. To report SUSPECTED ADVERSE REACTIONS, contact Bausch & Lomb Incorporated at 1-800-553-5340 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

CLINICAL PHARMACOLOGY Levobunolol hydrochloride is a noncardioselective beta-adrenoceptor blocking agent, equipotent at both beta 1 and beta 2 receptors. Levobunolol hydrochloride is greater than 60 times more potent than its dextro isomer in its beta-blocking activity, yet equipotent in its potential for direct myocardial depression. Accordingly, the levo isomer, levobunolol hydrochloride, is used. Levobunolol hydrochloride does not have significant local anesthetic (membrane-stabilizing) or intrinsic sympathomimetic 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. Beta-adrenergic receptor blockade in the bronchi and bronchioles results in increased airway resistance from unopposed parasympathetic activity. Such an effect in patients with asthma or other bronchospastic conditions is potentially dangerous. Levobunolol hydrochloride ophthalmic solution, USP has been shown to be an active agent in lowering elevated as well as normal intraocular pressure (IOP) whether or not accompanied by glaucoma. Elevated IOP presents a major risk factor in glaucomatous field loss. The higher the level of IOP, the greater the likelihood of optic nerve damage and visual field loss. The onset of action with one drop of levobunolol hydrochloride ophthalmic solution can be detected within one hour after treatment, with maximum effect seen between 2 and 6 hours. A significant decrease in IOP can be maintained for up to 24 hours following a single dose. In controlled clinical studies of approximately two years duration, intraocular pressure was well-controlled in approximately 80% of subjects treated with levobunolol hydrochloride ophthalmic solution 0.5% twice a day. The mean IOP decrease from baseline was between 7 mm Hg and 8 mm Hg. No significant effects on pupil size, tear production or corneal sensitivity were observed. Levobunolol hydrochloride ophthalmic solution at the concentrations tested, when applied topically, decreased heart rate and blood pressure in some patients. The IOP-lowering effect of levobunolol hydrochloride ophthalmic solution was well maintained over the course of these studies. In a three-month clinical study, a single daily application of 0.5% levobunolol hydrochloride ophthalmic solution controlled the IOP of 72% of subjects achieving an overall mean decrease in IOP of 7.0 mm Hg. The primary mechanism of the ocular hypotensive action of levobunolol hydrochloride in reducing IOP is most likely a decrease in aqueous humor production. Levobunolol hydrochloride ophthalmic solution reduces IOP with little or no effect on pupil size or accommodation.