LASIK is one of the most studied elective procedures in medicine, and the data consistently shows it’s safe for the vast majority of candidates. Patient satisfaction rates sit around 94%, and serious complications that threaten vision occur in fewer than 1% of cases. That said, “safe” doesn’t mean risk-free, and the outcome depends heavily on whether you’re a good candidate in the first place.
What the Satisfaction Numbers Actually Show
A large meta-analysis published in the Journal of Advanced Trends in Medical Research found an overall satisfaction rate of about 94% across studies using standard questionnaires, with a dissatisfaction rate of roughly 6%. Earlier reviews covering data from 1995 to 2003 showed similar numbers: 95.4% satisfaction after primary LASIK, with nearly identical rates for people correcting nearsightedness and farsightedness.
That 6% dissatisfaction figure matters, though. For a procedure performed on millions of people, 6% represents a meaningful number of individuals dealing with outcomes they didn’t expect. Dissatisfaction doesn’t always mean something went wrong clinically. It can reflect unmet expectations, residual need for glasses in certain situations, or lingering side effects like dry eyes or visual disturbances at night.
Dry Eye: The Most Common Side Effect
Dry eye is far and away the most frequent complaint after LASIK. Research published in the journal Ophthalmology found that chronic dry eye affects 20% to 40% of patients at least six months after surgery. For most people, the dryness is mild and manageable with artificial tears for the first few months. But some patients experience longer-lasting symptoms tied to nerve fiber changes in the cornea that can take years to fully recover.
If you already have significant dry eye before surgery, it’s considered a contraindication. Poorly controlled dry eye is on the list of absolute disqualifiers for LASIK, so your surgeon should screen for it during the preoperative exam. Mild pre-existing dryness is more of a gray area and worth a thorough conversation with your doctor.
Serious Complications Are Rare
The complication that concerns surgeons most is corneal ectasia, a progressive thinning and bulging of the cornea that can seriously impair vision. The reported incidence ranges from 0.04% to 0.6%, making it uncommon but not negligible. The biggest predictor is abnormal corneal shape before surgery, particularly undiagnosed or borderline keratoconus (a condition where the cornea is already weakening). Other risk factors include having a thin cornea, younger age, eye rubbing habits, family history of keratoconus, and male gender.
Modern screening has gotten much better at catching these risk factors. Surgeons now use detailed corneal mapping to measure thickness and shape, and they follow specific thresholds: a minimum preoperative corneal thickness of 470 micrometers, enough remaining corneal tissue after the procedure (at least 300 micrometers), and removal of no more than 20% of the central corneal thickness. When these limits are respected, the risk of ectasia drops substantially.
Other rare but possible complications include flap-related problems during surgery, infection, and persistent visual disturbances like halos or starbursts around lights. Night vision issues are common in the early weeks but typically resolve as the eyes heal.
Bladeless Technology Has Improved Safety
LASIK involves creating a thin flap on the cornea’s surface, then reshaping the tissue underneath with a laser. Older techniques used a mechanical blade (microkeratome) to create the flap. Modern “bladeless” LASIK uses a femtosecond laser instead, and the safety improvements are meaningful.
The American Academy of Ophthalmology notes that mechanical blades are susceptible to power loss, jamming, loss of suction during the cut, and operator error during assembly. Unusually shaped eyes also carry a higher risk of irregular flap creation with blades. Femtosecond lasers eliminate most of these failure modes and allow surgeons to precisely specify flap size and position. The latest generation systems operate at higher speeds with lower energy, which reduces inflammation and other flap-related complications. If you’re comparing clinics, asking whether they use femtosecond laser flap creation is a reasonable question.
How LASIK Compares to Contact Lenses
One useful way to think about LASIK safety is comparing it to the alternative most people are already using. Contact lenses carry their own risks, particularly microbial keratitis, a serious corneal infection. Research comparing the two found that just one year of extended-wear soft contact lens use led to three times as many cases of microbial keratitis as LASIK. Over a lifetime of contact lens wear, the cumulative infection risk adds up considerably. This doesn’t mean LASIK is automatically the safer choice for everyone, but it puts the risk in practical perspective.
Who Should Not Get LASIK
The safety of LASIK depends enormously on patient selection. Absolute contraindications include:
- Age under 18, because the eyes are still changing
- Unstable prescription, meaning your vision is still shifting year to year
- Keratoconus or other corneal diseases that weaken the cornea’s structure
- Poorly controlled dry eye
- Active autoimmune disease or poorly controlled diabetes, which impair healing
- Insufficient corneal thickness for the amount of correction needed
- Uncontrolled glaucoma or significant cataracts
- Unrealistic expectations, which the American Academy of Ophthalmology formally lists as a contraindication
Relative contraindications, meaning the procedure might still be possible but requires extra caution, include pregnancy or breastfeeding, age 18 to 21, use of certain medications like isotretinoin (commonly prescribed for acne) or amiodarone (a heart rhythm drug), history of eye inflammation, and having only one functional eye.
What Recovery Looks Like
Recovery is faster than most people expect. Most patients can drive within 24 hours and return to work in one to three days. You can shower the next day, though you’ll need to keep soap and shampoo out of your eyes for the first week. Eye makeup should wait a full week.
Physical activity follows a graduated timeline. Light exercise like walking or a stationary bike is fine within three to seven days, as long as you keep sweat out of your eyes. Jogging and light weights can resume after about a week. Heavy lifting and intense workouts typically get the green light at one to two weeks, with a gradual ramp-up in intensity. The main concern during early recovery is anything that raises eye pressure or risks contact with your eyes.
Vision improvement is often noticeable within hours, but full stabilization takes longer. Some patients experience fluctuating clarity, light sensitivity, and nighttime halos during the first few weeks. These effects are part of the normal healing process and gradually resolve for most people.
The FDA’s Role in LASIK Oversight
The FDA approves the lasers used in LASIK and has taken an active role in monitoring how the procedure is marketed. In 2009 and again in 2011, the FDA issued letters to eye care professionals warning them about failing to adequately inform patients of the risks, limitations, and contraindications of the procedure. The agency also contacted the major professional societies in refractive surgery to push for more balanced advertising. If a clinic’s marketing makes LASIK sound completely risk-free or glosses over side effects, that’s a red flag worth paying attention to.
A thorough preoperative evaluation, including detailed corneal mapping, dry eye testing, and an honest discussion of what results you can realistically expect, is the single best predictor of a safe outcome. The procedure itself has a strong track record, but it’s only as safe as the screening process that determines whether you should have it in the first place.