Last reviewed 2026-05-15 · How we verify

brimonidine 0.1% (Alphagan® P)

Brimonidine is an alpha-2 adrenergic receptor agonist that reduces intraocular pressure by decreasing aqueous humor production and increasing uveoscleral outflow in the eye.

Brimonidine is an alpha-2 adrenergic receptor agonist that reduces intraocular pressure by decreasing aqueous humor production and increasing uveoscleral outflow in the eye. Used for Open-angle glaucoma, Ocular hypertension.

At a glance

Mechanism of action

Brimonidine selectively binds to alpha-2 adrenergic receptors on the ciliary body and trabecular meshwork of the eye. This activation reduces the production of aqueous humor (the fluid inside the eye) and enhances its drainage through the uveoscleral pathway, thereby lowering intraocular pressure. The 0.1% formulation (Alphagan P) is optimized for topical ocular administration with improved tolerability.

Approved indications

• Open-angle glaucoma
• Ocular hypertension

Common side effects

• Ocular hyperemia (redness)
• Ocular pruritus (itching)
• Dry mouth
• Allergic conjunctivitis
• Blurred vision
• Headache

Key clinical trials

• A Safety and Efficacy Study of ALPHAGAN® P and LUMIGAN® in Subjects Previously Treated With Latanoprost for Glaucoma and Ocular Hypertension (PHASE4)
• 24-hour IOP-lowering Effect of Brimonidine 0.1% (PHASE4)
• Brimonidine 0.1% Versus Brinzolamide 1% as Adjunctive Therapy to Latanoprost 0.005% (PHASE4)

Primary sources

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Competitive intelligence

For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:

• brimonidine 0.1% (Alphagan® P) CI brief — competitive landscape report
• brimonidine 0.1% (Alphagan® P) updates RSS · CI watch RSS
• Allergan portfolio CI