Brands, Medical Use, Clinical Data
- Antihypertensive Agents
- EENT Drugs
Brands / Synonyms
Alphagan; Alphagan P; Brimonidine tartrate; Bromoxidine
For the lowering of intraocular pressure in patients with open-angle glaucoma or ocular hypertension.
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.
Minimal systemic absorption occurs after ocular insertion.
Oral LD50 is 50 mg/kg in mice and 100 mg/kg in rats.
Biotrnasformation / Drug Metabolism
Metabolized primarily by the liver.
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.
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.