Timolol

What it is used for

Betimol ® is indicated in the treatment of elevated intraocular pressure in patients with ocular hypertension or open-angle glaucoma.

How to take it

Betimol® Ophthalmic Solution is available in concentrations of 0.25% and 0.5%. The usual starting dose is one drop of 0.25% Betimol® in the affected eye(s) twice a day. If the clinical response is not adequate, the dosage may be changed to one drop of 0.5% solution in the affected eye(s) twice a day.

If the intraocular pressure is maintained at satisfactory levels, the dosage schedule may be changed to one drop once a day in the affected eye(s). Because of diurnal variations in intraocular pressure, satisfactory response to the once-a-day dose is best determined by measuring the intraocular pressure at different times during the day.

Since in some patients the pressure-lowering response to Betimol® may require a few weeks to stabilize, evaluation should include a determination of intraocular pressure after approximately 4 weeks of treatment with Betimol®.

Dosages above one drop of 0.5% Betimol® twice a day generally have not been shown to produce further reduction in intraocular pressure. If the patient's intraocular pressure is still not at a satisfactory level on this regimen, concomitant therapy with pilocarpine and other miotics, and/or epinephrine, and/or systemically administered carbonic anhydrase inhibitors, such as acetazolamide, can be instituted.

Side effects, and when to stop

The most frequently reported ocular event in clinical trials was burning/stinging on instillation and was comparable between Betimol ® and timolol maleate (approximately one in eight patients).

The following adverse events were associated with use of Betimol ® in frequencies of more than 5% in two controlled, double-masked clinical studies in which 184 patients received 0.25% or 0.5% Betimol ®:

OCULAR:

Dry eyes, itching, foreign body sensation, discomfort in the eye, eyelid erythema, conjunctival injection, and headache.

BODY AS A WHOLE:

Headache.

The following side effects were reported in frequencies of 1 to 5%:

OCULAR:

Eye pain, epiphora, photophobia, blurred or abnormal vision, corneal fluorescein staining, keratitis, blepharitis and cataract.

BODY AS A WHOLE:

Allergic reaction, asthenia, common cold and pain in extremities.

CARDIOVASCULAR:

Hypertension.

DIGESTIVE:

Nausea.

METABOLIC/NUTRITIONAL:

Peripheral edema.

NERVOUS SYSTEM/PSYCHIATRY:

Dizziness and dry mouth.

RESPIRATORY:

Respiratory infection and sinusitis.

In addition, the following adverse reactions have been reported with ophthalmic use of beta blockers:

OCULAR:

Conjunctivitis, blepharoptosis, decreased corneal sensitivity, visual disturbances including refractive changes, diplopia and retinal vascular disorder.

BODY AS A WHOLE:

Chest pain.

CARDIOVASCULAR:

Arrhythmia, palpitation, bradycardia, hypotension, syncope, heart block, cerebral vascular accident, cerebral ischemia, cardiac failure and cardiac arrest.

DIGESTIVE:

Diarrhea.

ENDOCRINE:

Masked symptoms of hypoglycemia in insulin dependent diabetics (See WARNINGS ).

NERVOUS SYSTEM/PSYCHIATRY:

Depression, impotence, increase in signs and symptoms of myasthenia gravis and paresthesia.

RESPIRATORY:

Dyspnea, bronchospasm, respiratory failure and nasal congestion.

SKIN:

Alopecia, hypersensitivity including localized and generalized rash, urticaria.

Who should not take it

Betimol ® is contraindicated in patients with overt heart failure, cardiogenic shock, sinus bradycardia, second- or third-degree atrioventricular block, bronchial asthma or history of bronchial asthma, or severe chronic obstructive pulmonary disease, or hypersensitivity to any component of this product.

Warnings

As with other topically applied ophthalmic drugs, Betimol ® is absorbed systemically. The same adverse reactions found with systemic administration of beta-adrenergic blocking agents may occur with topical administration. For example, severe respiratory and cardiac reactions, including death due to bronchospasm in patients with asthma, and rarely, death in association with cardiac failure have been reported following systemic or topical administration of beta-adrenergic blocking agents.

Storing it

Store between 15° to 25°C (59° to 77°F). Do not freeze. Protect from light.

General

Because of the potential effects of beta-adrenergic blocking agents relative to blood pressure and pulse, these agents should be used with caution in patients with cerebrovascular insufficiency. If signs or symptoms suggesting reduced cerebral blood flow develop following initiation of therapy with Betimol ®, alternative therapy should be considered.

There have been reports of bacterial keratitis associated with the use of multiple dose containers of topical ophthalmic products. These containers had been inadvertently contaminated by patients who, in most cases, had a concurrent corneal disease or a disruption of the ocular epithelial surface. (See PRECAUTIONS, Information for Patients.)