Betoptic Information
Betoptic (Betaxolol) Description
Betoptic (Betaxolol) ® Sterile Ophthalmic Solution contains betaxolol hydrochloride, a cardioselective beta-adrenergic receptor blocking agent, in a sterile isotonic solution. Betaxolol hydrochloride is a white, crystalline powder, soluble in water, with a molecular weight of 343.89. The chemical structure is presented below:
Empirical Formula: CHNO•HCl Chemical Name: (±)-1-[p-[2-(Cyclopropylmethoxy)ethyl]phenoxy]-3-(isopropylamino)-2-propanol hydrochloride.
Each mL of Betoptic (Betaxolol) Ophthalmic Solution (0.5%) contains: : 5.6 mg betaxolol hydrochloride equivalent to betaxolol base 5 mg. : Benzalkonium Chloride 0.01%. : Edetate Disodium, Sodium Chloride, Hydrochloric Acid and/or Sodium Hydroxide (to adjust pH), and Purified Water. DM-00
Betoptic (Betaxolol) Clinical Pharmacology
Betaxolol HCl, a cardioselective (beta-1-adrenergic) receptor blocking agent, does not have significant membrane-stabilizing (local anesthetic) activity and is devoid of intrinsic sympathomimetic action. Orally administered beta-adrenergic blocking agents reduce cardiac output in healthy subjects and patients with heart disease. In patients with severe impairment of myocardial function, beta-adrenergic receptor antagonists may inhibit the sympathetic stimulatory effect necessary to maintain adequate cardiac function.
When instilled in the eye, Betoptic (Betaxolol) Ophthalmic Solution has the action of reducing elevated as well as normal intraocular pressure, whether or not accompanied by glaucoma. Ophthalmic betaxolol has minimal effect on pulmonary and cardiovascular parameters.
Ophthalmic betaxolol (one drop in each eye) was compared to timolol and placebo in a three-way crossover study challenging nine patients with reactive airway disease who were selected on the basis of having at least a 15% reduction in the forced expiratory volume in one second (FEV) after administration of ophthalmic timolol. Betaxolol HCl had no significant effect on pulmonary function as measured by FEV. Forced Vital Capacity (FVC) and FEV/VC. Additionally, the action of isoproteranol, a beta stimulant, administered at the end of the study was not inhibited by ophthalmic betaxolol. In contrast, ophthalmic timolol significantly decreased these pulmonary functions.
No evidence of cardiovascular beta-adrenergic blockade during exercise was observed with betaxolol in a double-masked, three-way crossover study in 24 normal subjects comparing ophthalmic betaxolol, timolol and placebo for effect on blood pressure and heart rate. Mean arterial blood pressure was not affected by any treatment; however, ophthalmic timolol produced a significant decrease in the mean heart rate.
Betoptic (Betaxolol) Indications And Usage
Betoptic (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. It may be used alone or in combination with other anti-glaucoma drugs.
In clinical studies Betoptic (Betaxolol) was safely used to lower intraocular pressure in 47 patients with both glaucoma and reactive airway disease who were followed for a mean period of 15 months. However, caution should be used in treating patients with severe reactive airway disease or a history of asthma.
Betoptic (Betaxolol) Contraindications
Hypersensitivity to any component of this product. Betoptic (Betaxolol) Ophthalmic Solution is contraindicated in patients with sinus bradycardia, greater than a first degree atrioventricular block, cardiogenic shock, or patients with overt cardiac failure.
Betoptic (Betaxolol) Warning
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.
Betoptic (Betaxolol) ® Ophthalmic Solution 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 Betoptic (Betaxolol) Ophthalmic Solution should be discontinued at the first signs of cardiac failure.
Betoptic (Betaxolol) Precautions
Patients who are receiving a beta-adrenergic blocking agent orally and Betoptic (Betaxolol) 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 patients 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.
Betaxolol is an adrenergic blocking agent; therefore, caution should be exercised in patients using concomitant adrenergic psychotropic drugs.
Lifetime studies with betaxolol HCl have been completed in mice at oral doses of 6, 20 or 60 mg/kg/day and in rats at 3, 12, or 48 mg/kg/day; betaxolol HCl demonstrated no carcinogenic effect. Higher dose levels were not tested.
In a variety of and bacterial and mammalian cell assays, betaxolol HCl was nonmutagenic.
Pregnancy Category C.
Betoptic (Betaxolol) Adverse Reactions
The following adverse reactions have been reported in clinical trials with Betoptic (Betaxolol) Ophthalmic Solution.
Discomfort of short duration was experienced by one in four patients, but none discontinued therapy; occasional tearing has been reported. Rare instances of decreased corneal sensitivity, erythema, itching sensation, corneal punctate staining, keratitis, anisocoria, edema, and photophobia have been reported.
Additional medical events reported with other formulations of betaxolol include blurred vision, foreign body sensation, dryness of the eyes, inflammation, discharge, ocular pain, decreased visual acuity, and crusty lashes.
Betoptic (Betaxolol) Overdosage
No information is available on overdosage of humans. The oral LD of the drug ranged from 350-920 mg/kg in mice and 860-1050 mg/kg in rats. The symptoms which might be expected with an overdose of a systemically administered beta-1-adrenergic receptor blocker agent are bradycardia, hypotension and acute cardiac failure. A topical overdose of Betoptic (Betaxolol) Ophthalmic Solution may be flushed from the eye(s) with warm tap water.
Betoptic (Betaxolol) Dosage And Administration
The recommended dose is one to two drops of Betoptic (Betaxolol) Ophthalmic Solution in the affected eye(s) twice daily. In some patients, the intraocular pressure lowering responses to Betoptic (Betaxolol) Ophthalmic Solution may require a few weeks to stabilize. As with any new medication, careful monitoring of patients is advised.
If the intraocular pressure of the patient is not adequately controlled on this regimen, concomitant therapy with pilocarpine and other miotics, and/or epinephrine and/or carbonic anhydrase inhibitors can be instituted.
Betoptic (Betaxolol) How Supplied
Betoptic (Betaxolol) Ophthalmic Solution is a sterile, isotonic, aqueous solution of betaxolol hydrochloride. Supplied as follows: 2.5, 5, 10 and 15 mL in plastic ophthalmic DROP-TAINER® dispensers.
2.5 mL: NDC 0065-0245-20 10 mL: NDC 0065-0245-10
5 mL: NDC 0065-0245-05 15 mL: NDC 0065-0245-15
