|Trade names||Alphagan, Mirvaso, Lumify, others|
|topical (eye drop, gel)|
|Elimination half-life||3 hours (ocular), 12 hours (topical)|
|CompTox Dashboard (EPA)|
|Chemical and physical data|
|Molar mass||292.135 g/mol g·mol−1|
|3D model (JSmol)|
|Melting point||252 °C (486 °F)|
Common side effects when used in the eyes include itchiness, redness, and a dry mouth. Common side effects when used on the skin include redness, burning, and headaches. More significant side effects may include allergic reactions and low blood pressure. Use in pregnancy appears to be okay. When applied to the eye it works by decreasing the amount of aqueous humor made while increasing the amount that drains from the eye. When applied to the skin it works by causing blood vessels to contract.
Brimonidine was patented in 1972 and came into medical use in 1996. It is available as a generic medication. One milliliter in the United Kingdom costs the NHS about 1.13 £ as of 2019. In the United States the wholesale cost of this amount is about US$0.60. In 2016 it was the 167th most prescribed medication in the United States with more than 3 million prescriptions.
Brimonidine is indicated for the lowering of intraocular pressure in patients with open-angle glaucoma or ocular hypertension. It is also the active ingredient of brimonidine/timolol along with timolol maleate.
In 2013, the FDA approved topical application of brimonidine 0.33% gel for persistent facial redness of rosacea.
Peripheral α2 agonist activity results in vasoconstriction of blood vessels (as opposed to central α2 agonist activity that decreases sympathetic tone, as can be seen by the medication clonidine). This vasoconstriction may explain the acute reduction in aqueous humor flow. The increased uveoscleral outflow from prolonged use may be explained by increased prostaglandin release due to α adrenergic stimulation. This may lead to relaxed ciliary muscle and increased uveoscleral outflow.
It is under the brand names Alphagan, Alphagan-P, Mirvaso Lumify, others.
In July 2018, Bausch and Lomb began to market OTC eye drops, using brimonidine's tartrate formulation in a concentration of 0.025%, as an ophthalmic vasoconstrictor under the brand name Lumify. Intended to relieve redness in the sclerae of the eyes for periods of up to eight hours at a time through its vasoconstrictive effects, Lumify was marketed as an alternative to Visine, the brand of tetrahydrozoline hydrochloride solution most commonly used for that purpose.