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Alphagan Side Effects

Generic Name: brimonidine ophthalmic

Note: This page contains information about the side effects of brimonidine ophthalmic. Some of the dosage forms included on this document may not apply to the brand name Alphagan.

Not all side effects for Alphagan may be reported. You should always consult a doctor or healthcare professional for medical advice. Side effects can be reported to the FDA here.

For the Consumer

Applies to brimonidine ophthalmic: ophthalmic solution

In addition to its needed effects, some unwanted effects may be caused by brimonidine ophthalmic (the active ingredient contained in Alphagan). In the event that any of these side effects do occur, they may require medical attention.

You should check with your doctor immediately if any of these side effects occur when taking brimonidine ophthalmic:

More common
  • Blurred or loss of vision
  • burning, dry, or itching eyes
  • discharge or excessive tearing
  • disturbed color perception
  • double vision
  • halos around lights
  • headache
  • itching of the eye
  • night blindness
  • overbright appearance of lights
  • redness of the eye or inner lining of the eyelid
  • swelling of the eyelid
  • tearing of the eye
  • tunnel vision
Less common
  • Ache or pain in the eye
  • blindness
  • bloody eye
  • blurred vision or other change in vision
  • change in color vision
  • confusion
  • decreased vision
  • difficult or labored breathing
  • difficulty seeing at night
  • dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
  • drainage from the eye
  • fainting
  • fast heartbeat
  • feeling of something in the eye
  • gradual blurring or loss of vision
  • increased blood pressure
  • increased sensitivity of the eye to light
  • mental depression
  • muscle pain
  • nausea or vomiting
  • oozing in the eye
  • redness, swelling, or itching of the eye or eyelid
  • runny or stuffy nose
  • seeing flashes or sparks of light
  • seeing floating dark spots or material before eyes
  • seeing floating spots before the eyes or a veil or curtain appearing across part of vision
  • shortness of breath
  • skin rash
  • sneezing
  • sweating
  • swelling of the eye
  • tightness in the chest
  • unusual tiredness or weakness
  • watery eyes
  • wheezing
Incidence not known
  • Bluish lips or skin
  • chest pain or discomfort
  • confusion
  • fast, pounding, or irregular heartbeat or pulse
  • feeling of warmth or heat
  • flushing or redness of the skin, especially on the face and neck
  • irregular, fast, slow, or shallow breathing
  • low body temperature
  • muscle aches or weakness
  • shivering
  • slow or irregular heartbeat
  • weak or feeble pulse
  • weight gain

Some of the side effects that can occur with brimonidine ophthalmic may not need medical attention. As your body adjusts to the medicine during treatment these side effects may go away. Your health care professional may also be able to tell you about ways to reduce or prevent some of these side effects. If any of the following side effects continue, are bothersome or if you have any questions about them, check with your health care professional:

More common
  • Burning, stinging, or tearing of the eye
  • drowsiness or tiredness
  • dryness of the mouth
Less common
  • Acid or sour stomach
  • anxiety
  • bad, unusual, or unpleasant (after) taste
  • belching
  • body aches or pain
  • change in taste
  • chills
  • congestion
  • cough
  • cough producing mucus
  • crusting on eyelid or corner of eye
  • diarrhea
  • difficulty breathing
  • discoloration of white part of the eye
  • dryness of the eye
  • dryness or soreness of the throat
  • fever
  • general feeling of discomfort or illness
  • hoarseness
  • indigestion
  • joint pain
  • lack or loss of strength
  • large amounts of cholesterol in the blood
  • lid disorder
  • loss of appetite
  • muscle aches and pains
  • pain or tenderness around the eyes and cheekbones
  • paleness of the eye or inner lining of the eyelid
  • passing of gas
  • pounding heartbeat
  • rash
  • shivering
  • sleepiness or unusual drowsiness
  • sleeplessness
  • sneezing
  • sore throat
  • stomach discomfort, fullness, upset, or pain
  • tender, swollen glands in the neck
  • trouble with sleeping
  • trouble with swallowing
  • troubled breathing
  • unable to sleep
  • voice changes
Incidence not known
  • Constricted, pinpoint, or small pupils (black part of the eye)
  • redness of the skin
  • sensitivity to light
  • throbbing pain
  • unusual drowsiness, dullness, tiredness, weakness, or feeling of sluggishness
  • unusual weak feeling
  • unusually warm skin

For Healthcare Professionals

Applies to brimonidine ophthalmic: ophthalmic solution, topical gel


Anterior uveitis has been reported in at least 4 patients after 11 to 15 months of brimonidine treatment. Causality was confirmed by rechallenge.

There are no data on cases of uveitis involving brimonidine ophthalmic (the active ingredient contained in Alphagan) products with Purite as a preservative. Rather, case reports involve brimonidine products incorporating benzalkonium chloride as a preservative.[Ref]

Ocular side effects reported in 10% to 30% of patients have included ocular hyperemia, burning and stinging, blurring, foreign body sensation, conjunctival follicles, ocular allergic reactions and pruritus. Those reported in 3% to 9% of patients have included corneal staining/erosion, photophobia, eyelid erythema, ocular ache/pain, ocular dryness, tearing, eyelid edema, blepharitis, ocular irritation, conjunctival blanching, and abnormal vision. Lid crusting, uveitis, conjunctival hemorrhage, and conjunctival discharge have been reported in less than 3%. Brimonidine has been associated with elevated intraocular pressure (32 to 34 mmHg) in conjunction with a local allergic reaction.[Ref]


Gastrointestinal side effects have most frequently included oral dryness (10% to 30%). Other gastrointestinal side effects are uncommon.[Ref]

Nervous system

Nervous system side effects including fatigue/drowsiness and headache have occurred in 10% to 30% of patients. Other central nervous system side effects including dizziness have occurred in 3% to 9% of patients. Anxiety and insomnia have occurred in less than 3% of patients. Somnolence has been reported in infants.[Ref]


A study in young healthy adult males reported no change in pulmonary function after a single ophthalmic dose of 0.2% brimonidine.[Ref]

Upper respiratory symptoms were reported in 3% to 9% of patients receiving brimonidine ophthalmic. Nasal dryness was reported in less than 3% of patients.[Ref]


Cardiovascular side effects have included asthenia in 3% to 9% of patients. Other cardiovascular side effects such as hypertension, palpitations and syncope have occurred in less than 3% of patients.[Ref]

One study in young healthy adult men reported small decreases in systolic blood pressure during recovery from exercise and four hours after administration of a single ophthalmic dose of 0.2% brimonidine. The changes did not produce clinically significant effects in the population studied.[Ref]


Psychiatric side effects including depression and anxiety have been reported in less than 3% of patients.[Ref]


Musculoskeletal side effects including muscular pain have been reported in 3% to 9% of patients.[Ref]


Hypersensitivity reactions including sore red eyes, follicular reaction, conjunctival and episcleral injection, have rarely been reported.[Ref]


1. Byles DB, Frith P, Salmon JF "Anterior uveitis as a side effect of topical brimonidine." Am J Ophthalmol 130 (2000): 287-91

2. Schuman JS "Clinical experience with brimonidine 0.2% and timolol 0.5% in glaucoma and ocular hypertension." Surv Ophthalmol 41 ( Suppl (1996): s27-37

3. "Product Information. Alphagan (brimonidine ophthalmic)." Allergan Inc, Irvine, CA.

4. Becker HI, Walton RC, Diamant JI, Zegans ME "Anterior uveitis and concurrent allergic conjunctivitis associated with long-term use of topical 0.2% brimonidine tartrate." Arch Ophthalmol 122 (2004): 1063-6

5. Mushtaq B, Sardar J, Matthews TD "A paradoxical ocular effect of brimonidine." Am J Ophthalmol 135 (2003): 102-3

6. Levy Y, Zadok D "Systemic side effects of ophthalmic drops." Clin Pediatr (Phila) 43 (2004): 99-101

7. Nordlund JR, Pasquale LR, Robin AL, Rudikoff MT, Ordman J, Chen KS, Walt J "The cardiovascular, pulmonary, and ocular hypotensive effects of 0.2% brimonidine." Arch Ophthalmol 113 (1995): 77-83

8. Pang KS, Chery WF, Ulm EH "Disposition of enalapril in the perfused rat intestine-liver preparation: absorption, metabolism and first-pass effect." J Pharmacol Exp Ther 233 (1985): 788-95

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