Betaxol

Betaxolol ophthalmic solution has been shown to be effective in lowering intraocular pressure and is indicated in the treatment of ocular hypertension and chronic open-angle glaucoma. May be used alone or in combination with other intraocular pressure-lowering medication.

Betaxolol is a selective (beta-1-adrenergic) receptor blocking agent that does not have significant membrane stabilizing (local anesthetic) activity and is free from intrinsic sympathomimetic action. When instilled into the eye, Betaxolol reduces elevated as well as normal intraocular pressure, whether or not accompanied by glaucoma. Optic nerve head damage and visual field loss are results of a sustained elevated intraocular pressure and poor ocular perfusion. The ocular hypotensive action of Betaxolol appears to be mediated by a reduction of aqueous production as demonstrated by tonography and aqueous flurophotometry. Betaxolol ophthalmic solution does not produce miosis or accommodative spasm which is frequently seen with miotic.

The onset of action with Betaxolol can generally be noted within 30 minutes and the maximal effect can usually be detected two hours after topical administration. A single dose provides a 12-hour reduction in intraocular pressure (IOP) and twice daily administration maintains the IOP below 22 mm Hg in most patients.

Patients who are receiving a beta-adrenergic blocking agent orally and Betaxolol Hydrochloride Ophthalmic Solution should be observed for a potential additive effect either on the intraocular pressure or on the known systemic effects of beta blockade. Close observation of the patient is recommended when a beta blocker is administered to patients receiving catecholamine-depleting drugs such as reserpine, because of possible additive effects and the production of hypotension and/or bradycardia. Caution should be exercised in patients using concomitant adrenergic psychotropic drugs. In patients with angle-closure glaucoma, the immediate treatment objective is to reopen the angle by constriction of the pupil with a miotic agent. Betaxolol has little or no effect on the pupil. When Betaxolol Hydrochloride Ophthalmic Solution is used to reduce elevated intraocular pressure in angle-closure glaucoma, it should be used with a miotic and not alone.

Ocular: Discomfort of short duration, occasional tearing has been reported. Rare instances of decreased corneal sensitivity, erythema, itching sensation, corneal punctuate staining, keratitis, edema and photophobia have been reported.

Systemic: Systemic reactions following administration of Betaxolol hydrochloride ophthalmic solution 0.5% have been rarely reported. These include:

• Cardiovascular: bradycardia, heart block, congestive heart failure.
• Respiratory: bronchospasm, respiratory failure.
• Others: Hives, toxic epidermal necrolysis, hair loss and glossitis.

There are no adequate & well controlled studies in pregnant women. Betaxolol ophthalmic solution should be used during pregnancy only if the potential benefit justifies the potential risk. It is not known whether Betaxolol is excreted in human milk. The risk of hypoglycemia & bradycardia in nursing infant has not been evaluated. Breast feeding is not recommended during treatment.

In patients with angle-closure glaucoma, the immediate treatment objective is to re-open the angle by constriction of the pupil with miotic agent. Betaxolol has no effect on the pupil; therefore, Betaxolol should be used with a miotic to reduce elevated intraocular pressure in angle-closure glaucoma. Beta-adrenergic blocking agents should be administered with caution in patients subjected to spontaneous hypoglycemia or to diabetic patients as these agents may mask the signs and symptoms of acute hypoglycemia.

Drugs for miotics and glaucoma

No information is available on overdosage. A topical overdosage of Betaxolol ophthalmic solution may be flushed from the eye(s) with warm tap water.

Store at room temperature. It is desirable that the content should not be used more than one month after first opening of the bottle.