Am I a Good Candidate for LASIK? Complete Eligibility Guide

Approximately 80-85% of people who seek LASIK are good candidates. The other 15-20% may qualify for alternative procedures like PRK, SMILE, or ICL instead. Here's a detailed breakdown of the requirements.

Age Requirements

Minimum age: 18 years (FDA requirement). However, most surgeons prefer patients to be 21 or older because:

• The eyes continue developing into the early twenties
• Prescriptions tend to stabilize by age 21-25
• Patients under 21 have higher rates of regression (vision changing back)

Upper age limit: There's no strict maximum age, but patients over 40 should understand that LASIK corrects distance vision, not reading vision. After age 40-45, presbyopia (age-related farsightedness) means you'll likely still need reading glasses even after LASIK.

Patients over 55-60 may be better candidates for lens-based procedures like refractive lens exchange or cataract surgery (if cataracts are present).

Prescription Requirements

LASIK can correct a wide range of refractive errors, but there are limits:

Myopia (Nearsightedness)

• FDA approved range: Up to -12.00 diopters
• Ideal range: -1.00 to -8.00 diopters
• Best outcomes: -1.00 to -6.00 diopters

Higher myopia requires more corneal tissue removal, which may not be safe for all patients.

Hyperopia (Farsightedness)

• FDA approved range: Up to +6.00 diopters
• Ideal range: +1.00 to +4.00 diopters

Hyperopia correction tends to have slightly higher regression rates than myopia correction.

Astigmatism

• FDA approved range: Up to 6.00 diopters
• Ideal range: Up to 4.00 diopters

Prescription Stability

Your prescription must be stable for at least 12 months (preferably 24 months). "Stable" means no change greater than 0.50 diopters. If your prescription is still changing, LASIK results may not last.

This is why most surgeons recommend waiting until at least age 21 — prescriptions typically stabilize in the early twenties.

Corneal Requirements

Corneal Thickness

Your cornea must be thick enough to safely create a flap and remove tissue. The average cornea is about 540-550 microns thick.

• Minimum for LASIK: 500 microns (after accounting for flap)
• Ideal: 520+ microns
• Thin corneas (<500 microns): May qualify for PRK or ICL instead

The surgeon must leave at least 250-300 microns of residual stromal bed after the procedure. This ensures long-term corneal stability and prevents a condition called ectasia.

Corneal Shape

Your cornea must have a regular, healthy shape. Conditions that disqualify candidates include:

• Keratoconus: Progressive corneal thinning and bulging — absolute contraindication
• Pellucid marginal degeneration: Similar to keratoconus
• Corneal scars: May affect visual outcomes
• Previous herpes eye infections: Risk of reactivation

These conditions are detected during pre-operative corneal topography mapping.

Eye Health Requirements

Dry Eye

Moderate-to-severe dry eye syndrome can disqualify you from LASIK because:

• LASIK temporarily worsens dry eye
• Dry eyes heal more slowly
• Outcomes may be less predictable

Mild dry eye may be treatable before surgery. If you have severe dry eye, ICL (which doesn't affect the cornea) may be a better option.

Pupil Size

Large pupils (over 7mm in darkness) were once considered a risk factor for post-LASIK glare and halos. Modern wavefront-guided lasers with larger treatment zones have largely eliminated this concern. However, it's still measured and considered during evaluation.

Other Eye Conditions

Conditions that may affect candidacy:

• Glaucoma: May still qualify depending on severity and control
• Cataracts: Lens replacement surgery is typically better
• Amblyopia (lazy eye): LASIK won't improve vision beyond what glasses provide
• Retinal problems: Must be evaluated individually

General Health Factors

Autoimmune Conditions

Uncontrolled autoimmune diseases can impair healing:

• Rheumatoid arthritis
• Lupus
• Sjögren's syndrome (causes severe dry eye)
• Multiple sclerosis

Well-controlled autoimmune conditions may not disqualify you — discuss with your surgeon.

Diabetes

Well-controlled diabetes: May qualify for LASIK if no diabetic retinopathy present.

Uncontrolled diabetes: Generally not candidates due to healing issues and unstable prescriptions.

Pregnancy and Nursing

Women who are pregnant or breastfeeding should wait. Hormonal changes during pregnancy can temporarily change your prescription and affect healing. Wait at least 3 months after stopping breastfeeding.

Medications

Certain medications may affect candidacy:

• Accutane (isotretinoin): Wait 6-12 months after stopping
• Corticosteroids: May affect healing
• Amiodarone: Can cause corneal deposits

What If I'm Not a LASIK Candidate?

Not qualifying for LASIK doesn't mean you can't get vision correction surgery. Alternatives include:

The Pre-Operative Evaluation

The only way to know definitively if you're a candidate is a comprehensive eye examination. During the evaluation, your surgeon will:

• Measure your exact prescription
• Map your cornea's shape (topography)
• Measure corneal thickness (pachymetry)
• Check pupil size in various lighting
• Evaluate tear film and dry eye
• Examine your retina and optic nerve
• Review your medical history

This evaluation takes 1-2 hours and provides all the information needed to determine your candidacy and the best procedure for your eyes.