brimonidine (Alphagan)

What is brimonidine, and how does it work (mechanism of action)?

Brimonidine is is an ophthalmic solution used for the treatment of one type of glaucoma, open-angle glaucoma. In this type of glaucoma, too much fluid (aqueous humor) is made within the eye and causes high pressures within the eye. The pressure damages the nerves in the eye responsible for vision, and this ultimately causes blindness. Brimonidine reduces the body's production of aqueous humor and increases the flow of aqueous humor out of the eye, resulting in a decrease in pressure. It accomplishes this by stimulating alpha type 2 receptors selectively in the eye with less effect on alpha type 2 receptors elsewhere in the body. It is the first drug of its class to be used for glaucoma. Brimonidine was approved by the FDA in 1996.

What brand names are available for brimonidine?

Alphagan P

Is brimonidine available as a generic drug?


Do I need a prescription for brimonidine?


What are the side effects of brimonidine?

Common side effects include:

Other important side effects of brimonidine include:

What is the dosage for brimonidine?

The usual dose is one drop into each affected eye three times daily with each application approximately 8 hours apart.

Is brimonidine safe to take if I'm pregnant or breastfeeding?

It is not known if brimonidine is secreted in breast milk.

What else should I know about brimonidine?

What preparations of brimonidine are available?

Ophthalmic solution: 0.1%, 0.15%, and 0.2%.

How should I keep brimonidine stored?

Brimonidine should be kept at room temperature, 15 C to 30 C (59 F to 86 F) and protected for direct light.


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Medically reviewed by John P. Cunha, DO, FACOEP; Board Certified Emergency Medicine


FDA Prescribing Information