Detailed Drug Information:

DRUG CLASS AND MECHANISM: Betaxolol is a beta-adrenergic blocking agent.

When taken by mouth, betaxolol and other beta-adrenergic blocking agents act mainly by blocking the action of the sympathetic (adrenergic) nervous system, for example, on the heart.

In addition to its effect on the heart, betaxolol reduces the pressure within the eye (intraocular pressure). This effect is thought to be caused by reducing the production of the liquid (which is called the aqueous humor) within the eye. The precise mechanism of this effect is not known. The reduction in intraocular pressure reduces the risk of damage to the optic nerve and loss of vision in patients with elevated intraocular pressure due to glaucoma.

Betaxolol was approved by the U.S. Food and Drug Administration (FDA) for ocular use as a 0.5% solution(Betoptic) in 1985 and as a 0.25% solution (Betoptic S) in 1989.

PREPARATIONS: Betoptic S and Betoptic are different preparations and different strengths.Betoptic S 0.25% as base is available in plastic squeeze-bottle dispensers: 2.5 mL, 5 mL, 10 mL, 15 mL.Betoptic 0.5% as base is similarly available in plastic squeeze-bottle dispensers : 2.5 mL, 5 mL, 10 mL, 15 mL.

STORAGE: These ophthalmic solutions should be kept upright at room temperature, 15-30°C (59-86°F) and protected from direct light. Shake well before using each time.

PRESCRIBED FOR: Betaxolol is used for the treatment of glaucoma. Note that the type of glaucoma for whichBetoptic S or Betoptic usually is prescribed is the chronic open-angle type of glaucoma. (Oral betaxolol tablets are used for treating high blood pressure and angina, but this dosage form is not discussed here.)

DOSING: Both hands should be washed before each use of betaxolol or any other eye medication. The head should be tilted back and the lower lid pulled down with the index finger to form a pouch. The tip of the squeeze bottle should not be touched to the eye or eyelid. The bottle should be squeezed slightly to allow the prescribed number of drops into the pouch. The eye is closed gently for 1 to 2 minutes without blinking. The usual dose is 1 to 2 drops into each affected eye twice daily. Safe use of beta blockers in children has not been established.

DRUG INTERACTIONS: Combined use of betaxolol ophthalmic solution (Betoptic,Betoptic S) with oral beta- adrenergic blocking agents such as, for example, propranolol (Inderal), atenolol (Tenormin), metoprolol (Lopressor) or carvedilol (Coreg) can result in additive effects. Thus, patients may experience excessively low blood pressure or reductions in heart rate. Beta blockers, including betaxolol, are not habit forming.

PREGNANCY: Although there are no human studies that have examined the effects of oral betaxolol on the fetus, animal studies have shown adverse effects. Therefore, the physician must weigh the potential risks to the fetus against the potential benefits to the mother. It is unknown if the small amount of betaxolol that penetrates into the blood after administration into the eye and affects the fetus. Safe use ofbetaxolol during pregnancy thus has not been established.

NURSING MOTHERS: It is not known whether betaxolol is excreted into breast milk. Safe use ofbetaxolol during nursing thus has not been established.

SIDE EFFECTS: Ophthalmic betaxolol can cause side effects which are usually mild and transient. The most common side effect is transient ocular (temporary eye) discomfort. Rarely, betaxolol eye drops can result in side effects that are seen with oral beta-adrenergic blockers. For example, persons can experience fatigue, insomnia, nausea, dizziness, lightheadedness, depression, slow heart rate, low blood pressure, cold extremities, and shortness of breath or wheezing.