LASIK with Dry Eyes: Candidacy, Risks, and Precautions

Why Dry Eye Is a Concern for LASIK

LASIK temporarily reduces tear secretion and corneal sensitivity by severing some of the corneal sensory nerves during flap creation. The corneal nerves signal the lacrimal glands to produce tears; when these signals are disrupted, tear production decreases. This effect is temporary — nerves regenerate over 3–12 months — but it causes a predictable worsening of dry eye symptoms in the early post-operative period. For patients who already have dry eye before LASIK, this temporary worsening can be significant and occasionally persistent.

Additionally, dry eye symptoms after LASIK can mimic undercorrection (blurry, fluctuating vision) and negatively affect the patient's perception of their surgical outcome. Well-managed pre- and post-operative dry eye treatment is essential for patient satisfaction. See our guide on dry eye syndrome for background on the condition.

Schirmer Test and TBUT Testing

Two primary tests assess dry eye risk before LASIK:

• Schirmer test: a paper strip placed under the lower eyelid measures aqueous tear production over 5 minutes. Normal: ≥10 mm wetting; borderline: 5–10 mm; severe deficiency: <5 mm.
• Tear breakup time (TBUT): fluorescein dye is placed on the eye and the time until the first dry spot appears in the tear film is measured at the slit lamp. Normal: ≥10 seconds; borderline: 5–10 seconds; abnormal: <5 seconds.
• Osmolarity testing (TearLab): elevated tear osmolarity (≥308 mOsm/L) indicates tear film instability even when Schirmer and TBUT are borderline normal.
• MMP-9 testing (InflammaDry): detects inflammatory markers in the tear film associated with chronic dry eye disease.

Candidacy by Dry Eye Severity

Dry Eye Severity	Schirmer Result	TBUT	LASIK Candidacy
None / Minimal	≥10 mm	≥10 sec	Standard candidate
Mild	7–10 mm	7–10 sec	Candidate with pre-treatment and close monitoring
Moderate	5–7 mm	5–7 sec	Pre-treat first; SMILE may be preferred
Severe	<5 mm	<5 sec	LASIK contraindicated; PRK/SMILE with caution

Pre-Treatment Options Before LASIK

Patients with mild-to-moderate dry eye can often be optimized for LASIK with pre-operative treatment:

• Artificial tears: preservative-free drops used 4–6 times daily to stabilize the tear film
• Cyclosporine (Restasis, Cequa): prescription drops that reduce ocular surface inflammation; may require 3–6 months to achieve full effect before surgery
• Lifitegrast (Xiidra): blocks inflammatory T-cell activity; available as twice-daily drops
• Omega-3 supplementation: dietary omega-3 fatty acids improve meibomian gland function and tear film quality
• LipiFlow or IPL: in-office treatments for meibomian gland dysfunction that improve the lipid layer of the tear film
• Punctal plugs: small silicone plugs inserted into the lacrimal puncta to reduce tear drainage and retain tears on the eye's surface

Dry Eye After LASIK: What to Expect

Even patients without pre-existing dry eye commonly experience some dry eye symptoms for the first 1–3 months after LASIK. Symptoms typically include fluctuating vision especially later in the day, a foreign body or gritty sensation, occasional burning, and light sensitivity. These are normal and expected consequences of corneal nerve disruption. Most patients find symptoms resolve significantly by 3 months and are fully resolved by 6–12 months as corneal nerves regenerate. See dry eye as a LASIK risk for the full post-operative picture.

SMILE as a Lower Dry Eye Risk Alternative

SMILE (Small Incision Lenticule Extraction) has a significantly lower dry eye impact than LASIK because it preserves the anterior corneal stroma and disrupts fewer corneal nerves. No flap is created; instead, a small lenticule of tissue is removed through a 2–3 mm arc incision. Studies comparing LASIK and SMILE consistently show lower tear secretion disruption, better Schirmer test scores, and lower TBUT reduction at 3 and 6 months post-operatively with SMILE. For patients with borderline dry eye who have a prescription within SMILE's treatment range (myopia up to -10 D), SMILE is often recommended over LASIK.

Making the Decision: Dry Eye and LASIK

The presence of dry eye does not automatically exclude you from refractive surgery — it changes which procedure is most appropriate and what preparation is needed. A thorough pre-operative dry eye evaluation is standard at responsible LASIK centers. If your evaluation reveals dry eye, work with your surgeon to treat it adequately before scheduling surgery, and ask specifically about SMILE and PRK as alternatives with lower dry eye impact. Review the full LASIK candidacy criteria to understand the complete picture.