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Low vision is an umbrella term for people who still have trouble reading, wa"...
Topically applied beta-adrenergic blocking agents 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.
BETAXON™ (levobetaxolol hydrochloride ophthalmic suspension) Ophthalmic Suspension has been shown to have a minor effect on heart rate and blood pressure in clinical studies. Caution should be used in treating patients with a history of cardiac failure or heart block. Treatment with BETAXON™ (levobetaxolol hydrochloride ophthalmic suspension) Ophthalmic Suspension should be discontinued at the first signs of cardiac failure.
Bronchospasm and Obstructive Pulmonary Disease
Caution should be exercised in the treatment of glaucoma patients with excessive restriction of pulmonary function. There have been reports of asthmatic attacks and pulmonary distress during betaxolol treatment. Although rechallenges of some such patients with ophthalmic betaxolol has not adversely affected pulmonary function test results, the possibility of adverse pulmonary effects in patients sensitive to beta-blockers cannot be ruled out.
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.
Consideration should be given to the gradual withdrawal of beta-adrenergic blocking agents prior to general anesthesia because of the reduced ability of the heart to respond to beta-adrenergically mediated sympathetic reflex stimuli.
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 receptor blocking agents may mask the signs and symptoms of acute hypoglycemia.
While taking beta-blockers, patients with a history of atopy or a history of severe anaphylactic reaction to a variety of allergens may be more reactive to repeated accidental, diagnostic, or therapeutic challenge with such allergens. Such patients may be unresponsive to the usual doses of epinephrine used to treat anaphylactic reactions.
In patients with angle-closure glaucoma, the immediate treatment objective is to reopen the angle by constriction of the pupil with a miotic agent. Racemic betaxolol has little or no effect on the pupil. It is expected that levobetaxolol will also have little or no effect on the pupil. When BETAXON™ (levobetaxolol hydrochloride ophthalmic suspension) Ophthalmic Suspension is used to reduce elevated intraocular pressure in angle-closure glaucoma, it should be used with a miotic and not alone.
Carcinogenesis, Mutagenesis, Impairment of Fertility
In lifetime studies in mice at oral doses of 6, 20 and 60 mg/kg/day and in rats at oral doses of 3, 12 and 48 mg/kg/day, betaxolol HCl demonstrated no carcinogenic effect. Levobetaxolol was not mutagenic in the Ames assay, chromosomal aberration, mouse lymphoma, and cell transformation assays in vitro. Levobetaxolol demonstrated potential mutagenicity in the sister chromatid exchange assay in Chinese Hamster Ovarian cell in vitro in the presence of metabolic activation systems.
Use In Specific Populations
Pregnancy Category C
Reproduction, teratology, and peri- and postnatal studies have been conducted with orally administered betaxolol HCl and levobetaxolol HCl in rats and rabbits. There was evidence of drug related postimplantation loss in rabbits with levobetaxolol HCl at 12 mg/kg/day and sternebrae malformations at 4 mg/kg/day. No other adverse effects on reproduction were noted at subtoxic dose levels.
There are no adequate and well-controlled studies in pregnant women. BETAXON™ (levobetaxolol hydrochloride ophthalmic suspension) Ophthalmic Suspension should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.
It is not known whether BETAXON™ (levobetaxolol hydrochloride ophthalmic suspension) Ophthalmic Suspension is excreted in human milk. Because many drugs are excreted in human milk, caution should be exercised when BETAXON™ (levobetaxolol hydrochloride ophthalmic suspension) Ophthalmic Suspension is administered to nursing women.
The safety and IOP-lowering effects of BETAXON™ (levobetaxolol hydrochloride ophthalmic suspension) Ophthalmic Suspension have been demonstrated in pediatric patients in a three-month controlled trial.
No overall differences in safety or effectiveness have been observed between elderly and other adult patients.
Last reviewed on RxList: 3/30/2010
This monograph has been modified to include the generic and brand name in many instances.
Additional Betaxon Information
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