Timolol Maleate: Uses,Dosage,Side Effects

Generic Name
Timolol Maleate
Therapeutic Class: Ophthalmic

Indications:
Timolol Maleate Ophthalmic Solution is indicated in the treatment of elevated intraocular pressure in patients with ocular hypertension or open-angle glaucoma.

Presentation:
Timolol Maleate 0.5 Sterile Eye Drops: Each ml contains Timolol Maleate BP equivalent to Timolol 5 mg.

Description:
Timolol Maleate ophthalmic solution is a non-selective beta-adrenergic receptor blocking agent. Timolol Maleate Ophthalmic Solution, when applied topically on the eye, has the action of reducing elevated as well as normal intraocular pressure, whether or not accompanied by glaucoma. The precise mechanism of the ocular hypotensive action of Timolol Maleate is not clearly established at this time. Tonography and fluorophotometry studies in man suggest that its predominant action may be related to reduced aqueous humour formation. However, in some studies, a slight increase in outflow facility was also observed.

Dosage & Administration:
The usual starting dose is one drop of Timolol Maleate  0.5 in the affected eye(s) twice a day. Since in some patients the pressure-lowering response to Timolol Maleate may require a few weeks to stabilize, evaluation should include a determination of intraocular pressure after approximately 4 weeks of treatment with Timolol Maleate.
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.
Dosages above one drop of Timolol Maleate  0.5 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 other agents (s) for lowering intraocular pressure can be instituted. The concomitant use of two topical beta-adrenergic blocking agents is not recommended.
Pediatric Use: Safety and effectiveness in pediatric patients have not been established.
Geriatric Use: No overall differences in safety or effectiveness have been observed between elderly and younger patients.

Side Effects:
The most frequently reported adverse experiences have been burning and stinging upon instillation.
Less frequent adverse effects with ocular administration of Timolol Maleate formulations are nausea, diarrhea, dyspepsia, anorexia, dry mouth, headache, asthenia/fatigue, chest pain, bradycardia, arrhythmia, hypotension, palpitation, cold hands and feet, systemic lupus erythematosus, dizziness, paresthesia, somnolence, insomnia, nightmares, signs, and symptoms of systemic allergic reactions, bronchospasm (predominantly in patients with pre-existing bronchospastic disease).

Precautions:
As with many topically applied ophthalmic drugs, this drug 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 reactions and cardiac reactions have been reported following systemic or ophthalmic administration of Timolol Maleate. Precautions should be exercised in patients with cardiac failure, cerebrovascular insufficiency, obstructive pulmonary disease, major surgery, diabetes mellitus, thyrotoxicosis, bacterial keratitis, angle-closure glaucoma, anaphylaxis, and muscle weakness.

Use in Pregnancy & Lactation:
Pregnancy: There are no adequate and well-controlled studies in pregnant women. Timolol should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.
Lactation: Timolol has been detected in breast milk following oral and ophthalmic drug administration. Because of the potential for serious adverse reactions from Timolol in nursing infants, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother.

Interaction:
Although Timolol used alone has little or no effect on pupil size, mydriasis resulting from concomitant therapy with Timolol Maleate and epinephrine has been reported occasionally. Drug interactions of Timolol Maleate have been noticed with concomitant administration of beta-adrenergic blocking agents (both oral and topical), calcium antagonists, catecholamine-depleting drugs, digitalis, quinidine, clonidine, injectable epinephrine.

Overdose:
There have been reports of inadvertent overdosage with Timolol Ophthalmic Solution resulting in systemic effects similar to those seen with systemic beta-adrenergic blocking agents such as dizziness, headache, shortness of breath, bradycardia, bronchospasm, and cardiac arrest.

Storage:
Store between 15-30° C. Avoid freezing and protect from light.
Reactions

Post a Comment

0 Comments