LASIK Risks and Side Effects: Common Symptoms, Rare Complications and Red Flags

Expected early effects are not the same as complications

Watering, burning, light sensitivity, fluctuating clarity and mild glare are common in the first hours or days. Dryness and night-vision symptoms may last longer while the surface and corneal nerves recover.

Expected does not mean ignore. Symptoms should trend in the right direction and be checked at scheduled visits. A markedly different eye or worsening course deserves contact with the surgeon.

Dryness, glare, halos and contrast

Corneal nerve interruption and postoperative inflammation can reduce tear stability. A rough tear film makes optics fluctuate and can amplify halos, ghosting or glare. Baseline eyelid-gland disease and long screen hours can increase symptoms.

Pupil size, optical zone, residual prescription and induced aberrations also influence night vision. Management starts by identifying the cause rather than assuming every complaint is permanent laser damage.

Flap and interface problems

Flap folds, displacement, interface inflammation, debris and epithelial ingrowth are specific to flap-based surgery. Many are uncommon and treatable when recognized early, but delayed review can make management more difficult.

Avoid rubbing the eyes and attend early follow-up. Significant trauma should be examined even years later because the flap interface remains anatomically identifiable.

Infection and inflammation

Microbial keratitis after LASIK is uncommon but potentially sight-threatening. Increasing pain, redness, discharge, light sensitivity or declining vision should not be self-treated with leftover drops.

Sterile interface inflammation can also reduce vision and may require urgent adjustment of medication or flap care. Only examination can reliably separate infection, inflammation and surface dryness.

Residual prescription and ectasia

Under-correction, over-correction or regression may leave a need for glasses or, in selected stable cases, enhancement. A residual number should be interpreted after the tear film and refraction stabilize.

Ectasia is progressive corneal weakening with increasing irregular astigmatism. Screening with tomography and tissue calculations reduces risk but cannot make it zero. Treatment may include corneal cross-linking and visual rehabilitation rather than simply more laser.

How risk is reduced

Risk reduction starts before surgery: stable refraction, reliable imaging, appropriate tissue planning, dry-eye treatment, medication and disease review, and realistic expectations. During and after surgery, calibration, sterile technique, correct drops and follow-up matter.

The FDA checklist emphasizes candidacy, risks, surgeon experience, equipment, informed consent and postoperative expectations. A good consultation discusses reasons not to proceed as openly as reasons to proceed.

• Do not hide contact-lens use or medications
• Read the consent before surgery day
• Arrange transport and follow the drop schedule
• Know the clinic’s urgent-contact route