Seeing halos around lights is sometimes harmless and sometimes a sign of an underlying eye condition. Whether it is normal or not depends on what is causing them, and a comprehensive eye exam is the most reliable way to identify the source.
Halos appear as bright circles or rings around a light source, either colored or white, and are most noticeable at night or in dim light when the pupils naturally dilate. Some patients describe a starburst pattern with rays spreading from the light, while others notice a soft, diffuse glow. They can affect one or both eyes and vary in size, color, and intensity. Noting when halos appear and how often gives your optometrist information that directly shapes the exam plan.
Common Causes of Seeing Halos Around Lights
The following causes appear most often in day-to-day optometric practice, listed from most to least common.
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Early cataracts. Clouding of the natural lens causes halos and increased glare, particularly when driving at night. The American Optometric Association identifies halos around lights as a recognizable early symptom of cataract formation.
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Dry eye and tear-film irregularity. A disturbed tear layer scatters light and produces intermittent halos, especially on waking or in dry environments. Dry eye is a leading source of fluctuating visual symptoms including excessive blinking, blurry vision, glare, and eye fatigue.
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Uncorrected or outdated prescription. When a glasses or contact lens prescription no longer matches the current refractive error, light scatters and can produce halos. An updated prescription frequently resolves the symptom entirely.
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Post-surgical effects (LASIK, PRK, intraocular lenses). Halos are a documented early side effect after corneal refractive surgery and intraocular lens placement. Most patients see significant improvement over the months following surgery. Multifocal intraocular lenses carry a higher rate of halo symptoms than monofocal designs, particularly at night.
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Corneal disease, swelling, infection, or foreign body. Any disruption of the corneal surface scatters incoming light and can produce halos.
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Lens changes from uncontrolled blood sugar. Elevated blood glucose increases the osmolarity of the aqueous humor, which draws fluid into the crystalline lens through osmotic shift. This causes the lens to swell and change its refractive index, producing halos and blurry vision until blood sugar can be stabilized.
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Acute angle-closure glaucoma. This is a medical emergency. Sudden halos accompanied by eye pain, redness, nausea, or headache indicate dangerously elevated intraocular pressure and require immediate emergency care. Do not wait for a routine appointment.
What You Can Check at Home
A few checks can help determine whether halos are linked to something straightforward or more difficult to address.
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Check for dry eyes. If halos improve with rewetting drops, schedule a complete dry eye evaluation with your provider. Often Meibomian Gland Dysfunction, or MGD is to blame. Getting to the root of your dry eye problem increases your chances of maintaining a healthy tear film throughout your lifetime.
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Test with glasses only. If halos disappeared after changing or removing contact lenses, switch to your regular glasses for a day or two. Maybe your contact lens prescription could use an update.
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Clean your lenses. Smudges and scratches on glasses scatter light and produce halo-like effects. Clean both surfaces with a microfiber cloth and recheck before assuming the symptom is clinical.
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Check the timing. Halos that appear only in specific lighting conditions and then resolve fully are more likely to reflect a refractive cause. Check to make sure your prescription is up to date. If not, schedule your routine eye exam, even if it has been less than one year. Halos that persist across all conditions or that arrived suddenly are more urgent.
When to See Your Optometrist
Schedule an appointment at Vision Source Rio or Vision Source Heights if any of the following apply.
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Halos persist for more than a few days, or appear for the first time without a clear cause.
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Halos occur alongside worsening vision, fading colors, or blurred vision.
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Halos make night driving or other daily tasks difficult.
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Halos appear with eye pain, headache, redness, nausea, or sudden vision impairment.
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Halos appear along with dry eye. Schedule a complete dry eye evaluation.
If halos arrive suddenly with severe eye pain, redness, nausea, or a rapid drop in vision, seek emergency care immediately. Do not wait for a scheduled appointment. These symptoms can indicate acute angle-closure glaucoma, which causes rapid and irreversible vision impairment if left untreated.
A comprehensive eye exam evaluates vision, pupil responses, intraocular pressure, corneal clarity, lens condition, tear quality, and retinal health along with binocularity testing. Based on these findings, your optometrist can recommend targeted treatment rather than a generic approach.
Treatment Options
Prescription
A current glasses or contact lens prescription frequently reduces halos that stem from refractive change. A contact lens refitting may also help if symptoms appear only while wearing your contact lenses.
Dry Eye Treatment
Lubricating drops, environmental adjustments, lid hygiene protocols, and in-office treatments like Lipiflow and IPL can reduce halos linked to tear-film instability. The appropriate approach depends on the severity and underlying cause of the dry eye.
Corneal or Medical Treatment
When halos stem from a corneal cause, antibiotics, anti-inflammatory medications, or therapies that reduce corneal swelling may be appropriate. Your optometrist will identify the cause before recommending a treatment path. You may even be a candidate for a cryopreserved amniotic membrane.
Cataract Surgery
When cataracts are the cause, your optometrist will refer you for a cataract surgery evaluation. Removing the clouded natural lens typically resolves cataract-related halos. The choice of intraocular lens affects the likelihood of post-operative halos, and your surgical team will review monofocal and multifocal options before the procedure. Your optometrist continues to provide care before and after surgery as part of the co-management process.
Post-Surgical Recovery
Halos following LASIK or intraocular lens placement often improve over 6 to 12 months as the eye adapts to the new optics. Your optometrist can monitor recovery progress and coordinate with your surgical provider if symptoms persist beyond the expected recovery window.
Tips for Safer Night Driving
If halos are mild and a comprehensive exam has already ruled out a serious cause, the following adjustments can make night driving more comfortable while treatment is underway.
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Glare-free treatments on glasses. Prescription lenses with glare-free treatment reduce the scatter that contributes to halo formation due to oncoming headlights.
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Clean your optics. Headlights, mirrors, and the windshield should be clean and properly aligned to minimize additional light scatter.
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Reduce dashboard brightness. Bright, high-contrast dashboard lighting at night creates a glare differential that makes haloing from oncoming lights more pronounced.
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Consider EyeZen Lenses. EyeZen lenses are digitally surfaced on the back of the lens to match up exactly to your corneal topography measurements, thus reducing the potential for halos at night and on screens. In addition they have blue blocking technology built directly into the lenses themselves. Not all lenses are created equal. Invest in those that offer the most comfortable visual experience.
Patients whose halos are severe enough to impair driving safety should not drive at night until a full evaluation has been completed and a management plan is in place.
Frequently Asked Questions
Are rainbow-colored halos more serious than white halos?
Colored halos can indicate corneal or lens conditions, including changes in intraocular pressure that affect angle structures in the eye. A prompt evaluation is recommended when halos are vividly colored or appear suddenly, rather than waiting to see if they resolve on their own, particularly if accompanied by headache.
I had LASIK. Should I be concerned about halos several months later?
Halos after LASIK typically improve over 6 to 12 months as the cornea stabilizes and the visual system adapts. If halos are still present past that recovery window, a return evaluation with your optometrist or surgical provider is warranted to determine whether further intervention is appropriate.
Can cataract surgery cause halos?
Yes, particularly with multifocal intraocular lenses, which divide incoming light across near and distance focal points. Many patients find that halo symptoms diminish over time as the brain adapts to the new lens optics. Patients who are sensitive to visual side effects may prefer a monofocal lens, which typically produces fewer halos but requires glasses for one focal range. Discussing lifestyle, visual demands, and tolerance for adaptation before surgery helps ensure the best lens choice for you.
When are halos a medical emergency?
Halos that arrive suddenly alongside severe eye pain, headache, redness, nausea, or rapid vision impairment constitute a medical emergency consistent with acute angle-closure glaucoma. This condition causes permanent vision loss within hours if intraocular pressure is not relieved promptly. See your optometrist, go to an emergency room or urgent eye care facility immediately.
What is the difference between halos and glare?
Glare is the discomfort or temporary visual impairment caused by a bright light source. Halos are the rings or starburst patterns that form around a light source. Both can occur together with cataracts, dry eye, or refractive changes, and both warrant evaluation when they persist or interfere with daily activity.
Schedule Your Annual Comprehensive Eye Exam
Whether or not seeing halos around lights is normal depends entirely on the underlying cause, and only a comprehensive eye exam can identify it. The optometrists at Vision Source Rio and Vision Source Heights evaluate the cornea, lens, tear film, intraocular pressure, and retinal health to find the source and recommend an appropriate treatment plan.
If halos arrive suddenly with pain, redness, nausea, or sudden vision impairment, seek emergency care immediately.
Schedule your annual eye exam at Vision Source Rio in Rio Rancho or Vision Source Heights in Albuquerque.
