Betaxolol

Brand names

• Betoptic
• Betoptic-Pilo [CD]
• Betoptic-S
• Kerlone
• Novo-Betaxolol
• Sab-Betaxolol

Usage

To treat glaucoma.

How it works

Glaucoma, a sight-threatening disorder, occurs when aqueous humor (the fluid inside the eye) cannot drain properly, resulting in an increase in pressure within the eyeball (known as intraocular pressure). Increased intraocular pressure (lOP) can damage the optic nerve and lead to a gradually progressive loss of vision. Betaxolol decreases the production of aqueous humor, thereby reducing intraocular pressure.

Side effects

Serious

Palpitations, trouble breathing, dizziness and weakness caused by low blood pressure.

Common

Temporary eye irritation, tearing, eye inflammation, burning, swelling.

Less common

Blurred vision, poor night vision, and increased sensitivity to light; headache; insomnia; sinus irritation; odd or bitter taste in the mouth.

Possible interactions

Other medicaments:

Betaxolol may increase the effects of:

• other antihypertensive medicaments and cause excessive lowering of blood pressure. Dosage decreases may be necessary.
• reserpine (Ser-Ap-Es, etc.) and cause sedation, depression, slowing of heart rate and lowering of blood pressure (light-headedness, fainting).
• verapamil and cause additive risk of congestive heart failure and slow heart rate (bradycardia}.

Betaxolol taken concurrently with:



• amiodarone (Cordarone) may result in extremely slow heart rate and arrest.
• calcium channel blockers (Diltiazem, etc.) may severely lower blood pressure.
• clonidine (Catapres) requires close monitoring for rebound high blood pressure if clonidine is stopped while betaxolol is still being taken.
• digoxin (Lanoxin) may prolong AV conduction time and digoxin toxicity.
• fluoroquinolone antibiotics may cause an increase in betaxolol blood levels and lead to toxicity.
• fluvoxamine (Luvox) may cause excessive slowing of the heart and very low blood pressure.
• insulin requires close supervision to avoid hypoglycemia.
• methyldopa (various) may lead to an exaggerated hypertensive response to stress.
• oral antidiabetic medicaments may prolong recovery from low blood sugars.
• phenothiazines may result in additive blood pressure lowering effects.
• rifabutin (Mycobutin) may decrease betaxolol benefits.
• ritonavir (Norvir) and perhaps other protease inhibitors may decrease betaxolol benefits.
• venlafaxine (Effexor) may cause excessive slowing of the heart and very low blood pressure.
• zileuton (Zyflo) may cause excessive blood pressure lowering.

The following medicaments may decrease the effects of betaxolol:



• indomethacin (Indocin) and possibly other "aspirin substitutes," or NSAIDs, may impair betaxolol's antihypertensive effect.

Herbal medicines or minerals:

Ginseng may increase blood pressure, blunting the benefits of this medicine. Hawthorn, saw palmetto, ma huang, goldenseal, yohimbe and licorice may also increase blood pressure. Calcium and garlic may help lower blood pressure. Indian snakeroot has a German Commission E monograph indication for hypertension-talk to your doctor. Eleuthero root and ephedra should be avoided by people living with hypertension. Belladonna, ephedra, henbane leaf and scopolia root should be avoided by people living with glaucoma.

Alcohol:

Use with caution. Alcohol may exaggerate lowering of blood pressure and may increase its mild sedative effect.

Tobacco smoking:

Nicotine may reduce this medicament's effectiveness. High medicament doses worsen bronchial constriction caused by regular smoking.

Exposure to heat:

Caution is advised. Hot environments can lower blood pressure and exaggerate the effects of this medicament.

Exposure to cold:

Caution is advised. Cold environments can enhance the circulatory deficiency in the extremities that may occur with this medicament. The elderly should be careful to prevent hypothermia.

Heavy exercise or exertion:

Talk with your doctor about an exercise program that is right for you, mindful of this medicine and your physical condition.

Occurrence of unrelated illness:

Fever can lower blood pressure and require dosing changes. Nausea or vomiting may interrupt dosing. Ask your doctor for help.

Discontinuation:

Do not stop this medicament suddenly. Gradual physician-supervised dose reduction over 2 to 3 weeks is recommended.