Active ingredient: Brimonidine - Brands, Medical Use, Clinical Data

Brands, Medical Use, Clinical Data

Drug Category

• Antihypertensive Agents
• EENT Drugs

Dosage Forms

• 0.2% solution

Brands / Synonyms

Alphagan; Alphagan P; Brimonidine tartrate; Bromoxidine ; Combigan

Indications

For the lowering of intraocular pressure in patients with open-angle glaucoma or ocular hypertension.

Pharmacology

Brimonidine significantly lowers intraocular pressure with minimal effects on cardiovascular and pulmonary parameters. It lowers intraocular pressure by reducing aqueous humor production and increasing uveoscleral outflow.

Mechanism of Action

Brimonidine is an alpha adrenergic receptor agonist. It has a peak ocular hypotensive effect occurring at two hours post-dosing. Fluorophotometric studies in animals and humans suggest that Brimonidine has a dual mechanism of action by reducing aqueous humor production and increasing uveoscleral outflow.

Absorption

Minimal systemic absorption occurs after ocular insertion.

Toxicity

Oral LD₅₀ is 50 mg/kg in mice and 100 mg/kg in rats.

Biotrnasformation / Drug Metabolism

Metabolized primarily by the liver.

Contraindications

ALPHAGAN^® P is contraindicated in patients with hypersensitivity to brimonidine tartrate or any component of this medication. It is also contraindicated in patients receiving monoamine oxidase (MAO) inhibitor therapy.

Drug Interactions

Although specific drug interaction studies have not been conducted with ALPHAGAN^® P, the possibility of an additive or potentiating effect with CNS depressants (alcohol, barbiturates, opiates, sedatives, or anesthetics) should be considered. Alpha-agonists, as a class, may reduce pulse and blood pressure. Caution in using concomitant drugs such as beta-blockers (ophthalmic and systemic), anti-hypertensives and/or cardiac glycosides is advised.

Tricyclic antidepressants have been reported to blunt the hypotensive effect of systemic clonidine.It is not known whether the concurrent use of these agents with ALPHAGAN^® P in humans can lead to resulting interference with the IOP lowering effect. No data on the level of circulating catecholamines after ALPHAGAN^® P administration are available. Caution, however, is advised in patients taking tricyclic antidepressants which can affect the metabolism and uptake of circulating amines.