Can I Get LASIK If I Have Astigmatism or a High Prescription?

If you’ve been told in the past that you’re not a candidate for LASIK because of astigmatism or a high prescription, the good news is: that may no longer be true. Advancements in laser technology have dramatically expanded who qualifies for laser vision correction.

At Peninsula Laser Eye Medical Group, we evaluate patients every day who are surprised to learn that LASIK—or another modern refractive option—may be possible for them, even with complex prescriptions.

Still, LASIK isn’t one-size-fits-all. Here’s what you need to know.

Can LASIK Correct Astigmatism?

Yes, LASIK can treat astigmatism—as long as your corneas meet certain health and thickness requirements.

Astigmatism is caused by an irregular curvature of the cornea, which leads to blurred or distorted vision at all distances. During LASIK, the excimer laser reshapes the cornea to make it more symmetrical, allowing light to focus properly on the retina.

Medically accurate notes:

The FDA has approved LASIK to correct up to 6 diopters of astigmatism in most patients.
Custom wavefront-guided LASIK (a more precise form of laser correction) can improve results for those with irregular or asymmetric astigmatism.

Not all types of astigmatism are LASIK-correctable, so a full corneal mapping (topography) is essential to determine candidacy.

What If I Have a High Prescription?

LASIK is FDA-approved for:

Myopia (nearsightedness): up to -12.00 diopters (depending on corneal thickness)
Hyperopia (farsightedness): up to +6.00 diopters
Astigmatism: up to 6.00 diopters

If your prescription is at the upper end of that range—or beyond—it doesn’t automatically disqualify you, but your corneal thickness and overall eye health become even more important.

In some cases, patients with high prescriptions may be better suited for:

PRK (Photorefractive Keratectomy) – no flap required, good for thinner corneas
Phakic IOLs (Implantable Contact Lenses) – used for extreme nearsightedness or when LASIK isn’t possible
Refractive Lens Exchange (RLE/CLR) – ideal for older patients with presbyopia or early lens changes

We never recommend a procedure unless it’s safe and appropriate for your specific anatomy.

What Makes Someone a LASIK Candidate?
LASIK candidacy depends on more than just your prescription. We look at:

Corneal thickness and shape
Tear film quality (for dry eye risk)
Pupil size in low light
Overall eye health (retina, lens, optic nerve)
Prescription stability over the last 12 months
Any history of eye disease, injury, or autoimmune conditions

If you’re not a good fit for LASIK, we’ll help you explore alternatives that are equally effective and FDA-cleared.

Why a Comprehensive Evaluation Matters

At Peninsula Laser Eye Medical Group in Mountain View, CA, we don’t rely on guesswork or assumptions. We use advanced diagnostics like:

Corneal topography and OCT imaging
Wavefront analysis
Pachymetry to measure corneal thickness
Dry eye testing and pupil measurement

These allow us to design the safest, most personalized treatment plan—whether that’s LASIK or another option.

Final Takeaway

Yes, many patients with astigmatism or high prescriptions can safely have LASIK, but it depends on several key medical factors. Thanks to modern technology and personalized surgical planning, options now exist for patients who were previously told “no.”

The only way to know for sure is to come in for a consultation.

Call (650) 961-2585 or schedule online to find out if you’re a candidate. Our Mountain View-based team will walk you through every option and help you take the next step toward glasses-free vision—safely, confidently, and without pressure.