LASIK Risks and Side Effects Explained

# LASIK Risks and Side Effects Explained

LASIK risks include temporary dry eye, glare, and halos around lights at night — the most commonly discussed side effects. Less common issues include overcorrection or undercorrection, corneal flap problems, and, rarely, lasting vision changes or vision loss. Most side effects fade with time, but some can persist. Understanding the full picture before deciding is essential.

Key takeaways

Every elective procedure carries risk — dry eye, glare, and halos at night are the most commonly discussed LASIK side effects.
Most side effects are temporary, but some can linger for months, and a small number of outcomes can be lasting.
Your personal risk profile is individual: pre-existing dry eye, thin corneas, large pupils, and unstable prescriptions can all raise risk.
A thorough consultation with measurements and candidacy screening is the main safeguard — discuss every concern with a qualified eye-care professional.
Enhancements (touch-up procedures) can correct some residual refractive errors, but they add their own risk and cost considerations — ask about them before surgery, not after.

Why the risk conversation comes first

balanced abstract illustration — LASIK Risks and Side Effects Explained

It is tempting to research LASIK the way you research a purchase — compare prices, read about the technology, look at results. But LASIK is a surgical procedure on your eyes, and the responsible starting point is always the risk side of the ledger, not the cost side.

That is not meant to frighten you. It is meant to put you in the strongest possible position. Patients who understand the risks before their consultation ask better questions, recognize red flags in high-pressure sales environments, and make decisions they feel good about years later.

Everything in this article is educational information. The frequency and severity of any side effect depends on your individual eyes, the technology used, and the practice — none of which a general guide can evaluate. Treat this page as preparation for a professional conversation, not a substitute for one. Our guide to what the LASIK consultation involves explains how that conversation usually unfolds.

The most commonly discussed side effects

Dry eye

Temporary dry eye is one of the most frequently discussed LASIK side effects. Creating the corneal flap can disrupt some of the corneal nerves that help regulate tear production. For many people, this shows up as a scratchy, gritty, or burning sensation in the weeks after surgery.

In most cases, dryness improves as the nerves recover, and practices commonly recommend artificial tears during that period. Some people — especially those who already had dry eye before surgery — experience dryness that lasts much longer. This is one reason pre-existing dry eye is a key part of candidacy screening.

Glare, halos, and starbursts

Many people notice glare, halos (rings around lights), or starbursts around bright light sources — particularly at night — in the weeks after LASIK. Headlights, street lamps, and backlit signs can look smeared or ringed while the cornea heals and the visual system adjusts.

For most people these effects diminish with time. For some, they persist and can be bothersome enough to affect night driving comfort. People with larger pupils, higher prescriptions, or pre-existing night-vision complaints tend to be counseled about this more carefully. If you do a lot of night driving, raise it specifically at your consultation.

Fluctuating or blurry vision

Vision that shifts between clear and hazy — sometimes hour to hour — is a common early healing experience as the cornea remodels and the tear film stabilizes. The direction of travel matters more than any single moment: gradual, steady improvement is the usual pattern. Vision that is getting worse, or that suddenly changes, should be reported to the practice promptly.

Light sensitivity

Heightened sensitivity to bright light is common in the early recovery period, which is why sunglasses are routinely recommended after the procedure. Light sensitivity typically fades as healing progresses.

Less common complications

person with eyes closed resting — LASIK Risks and Side Effects Explained

Overcorrection and undercorrection

The laser reshapes the cornea according to a calculated treatment plan, and sometimes the result lands slightly off target. Overcorrection means too much tissue was removed, leaving the eye slightly farsighted; undercorrection means too little was removed, leaving some residual nearsightedness or astigmatism.

Small residual errors may be correctable with an enhancement — a second, touch-up procedure. But enhancements have their own considerations: they require enough remaining corneal thickness, they add cost (ask whether enhancements are included in the quoted price or billed separately), and they restart the healing and risk cycle. Not everyone with a residual error is a candidate for enhancement.

Corneal flap issues

LASIK's defining feature is the thin corneal flap created at the start of the procedure. Flap-related complications — such as a flap that is cut irregularly, wrinkles, or shifts — are uncommon with modern equipment and experienced surgeons, but they are one of the reasons LASIK has a distinct risk profile compared to surface procedures like PRK.

Flap displacement is most relevant in the early healing period, which is why rubbing the eyes is restricted after surgery. Trauma to the eye years later can theoretically disturb a LASIK flap, though this is uncommon.

Infection and inflammation

Any surgical procedure that opens tissue carries some infection risk, though serious infection after LASIK is uncommon. Practices use sterile technique and typically prescribe antibiotic and anti-inflammatory drops after the procedure. Inflammation under the flap is a known, treatable complication when caught early — another reason follow-up visits are not optional.

Regression

In some cases, vision gradually drifts back toward the original prescription over months or years after LASIK. This regression is distinct from the normal age-related changes every eye undergoes. It cannot be predicted with certainty for any individual, which is why a stable prescription before surgery is part of candidacy evaluation.

Rare but serious outcomes

It would be dishonest to discuss LASIK risks without acknowledging the rare, serious end of the spectrum. These are uncommon, but real and documented:

Corneal ectasia: a progressive weakening and bulging of the cornea that can distort vision significantly. Modern screening (measuring corneal thickness and shape) is specifically designed to identify people at higher risk before surgery.
Persistent vision loss: a lasting reduction in best-corrected vision — meaning vision that cannot be fully restored even with glasses — is a rare but recognized risk.
Chronic pain or persistent dry eye: a small number of people report ongoing eye pain or dryness that does not resolve.

No ethical practice will promise you a risk-free outcome, and you should treat any marketing that implies one as a reason for caution rather than confidence. The honest framing is that LASIK has a strong safety record in properly selected patients — and that proper selection is doing most of the work in that sentence.

Factors that can raise your personal risk

Risk is not evenly distributed. The following factors commonly lead a practice to counsel extra caution, recommend a different procedure, or decline LASIK candidacy:

Pre-existing dry eye, especially moderate to severe or related to autoimmune conditions.
Thin corneas relative to the amount of correction needed — there must be enough tissue left after reshaping.
Unstable prescriptions — significant recent changes in glasses or contact lens prescription.
Certain corneal irregularities or diseases, such as keratoconus.
Large pupils in dim light, which can interact with nighttime visual symptoms.
Autoimmune diseases, which can affect healing.
Pregnancy or nursing, during which hormonal shifts can change the prescription.
Very high prescriptions, which require more tissue removal.

If you recognize yourself in this list, do not self-disqualify — and do not assume you are fine either. Our guide on who makes a good LASIK candidate and the companion piece on reasons you might not be a candidate walk through how practices weigh these factors.

How screening protects you

The consultation is where risk management actually happens. A thorough LASIK evaluation typically includes detailed corneal mapping, corneal thickness measurement, pupil size measurement, tear film assessment, a dilated eye exam, and a careful review of your prescription history and general health.

This is not paperwork — it is the mechanism by which unsuitable candidates are identified and turned away. A practice that rushes this stage, skips measurements, or seems eager to approve everyone is telling you something important about its priorities.

Cost and screening quality can interact in uncomfortable ways. Unusually cheap offers sometimes correlate with thinner evaluations or high-volume models. Our guide to what affects the cost of LASIK explains which cost differences reflect real value and which should raise questions.

Questions to ask about risks at your consultation

Bring these to your appointment. The answers — and how comfortably they are given — tell you a great deal:

Am I a good candidate, a borderline candidate, or not a candidate — and why?
What is my corneal thickness, and how much tissue will my correction require?
Do I show signs of dry eye now, and how does that change your recommendation?
What nighttime visual symptoms should I expect given my pupils and prescription?
What is your enhancement rate, and are enhancements included in the price?
Would you recommend PRK or another procedure instead of LASIK for me?
How many follow-up visits are included, and what happens if I have a complication?

A practice that welcomes these questions is demonstrating the culture you want. One that deflects them is demonstrating the opposite.

Keeping expectations realistic

LASIK corrects refractive error; it does not freeze your eyes in time. Presbyopia — the age-related loss of near focusing ability — will still arrive on its normal schedule, typically in the 40s, and LASIK does not prevent it. Cataracts, glaucoma, and other age-related eye conditions remain possible regardless of prior LASIK. And while many people achieve excellent uncorrected vision, "perfect" vision is not a promise any honest provider makes.

The most satisfied LASIK patients tend to share two traits: they were genuinely good candidates, and they went in with clear-eyed expectations.

Frequently asked questions

How common are serious complications from LASIK?

Serious complications are considered uncommon when patients are properly screened and treated with modern technology — but "uncommon" is not "impossible," and no honest source gives a single universal rate because outcomes depend on the patient population, the technology, and the practice. What matters for you is your personal risk profile. Ask the practice directly about its own complication and enhancement rates.

Will dry eye after LASIK go away?

For most people, post-LASIK dryness improves over the weeks to months after the procedure as corneal nerves recover, and artificial tears are commonly recommended during that window. However, some people experience dryness that lasts much longer, and those with pre-existing dry eye are at higher risk of persistent symptoms. A tear film assessment before surgery helps predict this — discuss your symptoms honestly at your consultation.

Can LASIK make my vision worse?

It is possible, though uncommon with proper screening. Overcorrection, undercorrection, induced astigmatism, persistent glare or halos, and in rare cases corneal ectasia or lasting vision loss can leave vision worse than before. This is the core reason candidacy screening exists: the best protection is being a genuinely suitable candidate treated conservatively. Never proceed with a practice that minimizes these possibilities.

What happens if I am not happy with my LASIK results?

First, allow the full healing period the practice advises before judging the outcome, since early fluctuations are normal. If a residual refractive error remains after healing, an enhancement procedure may be an option if your corneas have sufficient remaining thickness. For visual symptoms like glare or dryness, management options vary by cause. Ask before surgery what the practice's policy is on enhancements and complications.

Should I get LASIK if I have dry eye already?

Pre-existing dry eye is one of the more important risk factors to evaluate, because LASIK can temporarily worsen dryness and recovery may be longer. Mild dry eye does not automatically disqualify you — some practices treat it first and re-evaluate — but moderate to severe dry eye often leads to a recommendation against LASIK or toward a surface procedure. This decision requires an in-person tear film evaluation.

Your concrete next step

Write down your personal risk questions — dry eye history, night driving needs, prescription stability, any eye or autoimmune conditions — and bring them to a consultation with a qualified eye-care professional. The quality of the risk conversation is one of the most reliable signals of the quality of the care.

This site is educational information only — not medical advice. Consult a qualified eye-care professional about your own situation.