How Painful Is Corneal Cross-Linking?

It’s completely normal to feel nervous about any eye procedure and corneal cross-linking is no exception. Because it involves the surface of the eye and ultraviolet (UV) light, many patients wonder: “Will it hurt?”

The good news is that while corneal cross-linking (CXL) can cause temporary discomfort, most patients describe the experience as mild to moderate rather than truly painful. With modern anaesthetic drops and careful aftercare, recovery is typically smooth and well-tolerated.

In this article, we’ll explain exactly what to expect during and after corneal cross-linking treatment from how pain is managed, to what sensations are normal, and when to contact your eye specialist.

What Is Corneal Cross-Linking?

Corneal cross-linking is a procedure designed to strengthen the cornea, the clear dome-shaped surface at the front of your eye. It’s primarily used to stop the progression of keratoconus, a condition where the cornea thins and bulges outward into a cone shape.

The treatment involves applying vitamin B2 (riboflavin) drops to the cornea and then activating them with a controlled UV light. This interaction forms new collagen “cross-links,” which reinforce the corneal structure similar to adding more rivets to a bridge.

By increasing corneal stiffness, the procedure helps stabilise vision and prevent further deterioration.

The Two Main Types of Corneal Cross-Linking

Pain perception varies slightly depending on the technique used:

1. Epi-Off (Standard) Cross-Linking

This is the traditional approach, where the thin surface layer of the cornea the epithelium is gently removed before applying riboflavin. Removing this layer allows better absorption of the vitamin and UV light but also leads to more post-treatment sensitivity until the epithelium regrows.

2. Epi-On (Transepithelial) Cross-Linking

Here, the epithelium is left intact, making the procedure less invasive. It often causes less discomfort and a faster recovery, but the strengthening effect can be slightly reduced compared to epi-off methods.

Your surgeon will choose the best option for your condition and corneal thickness.

Step-by-Step: What You’ll Feel During the Procedure

Understanding what happens at each stage can help you feel more comfortable and confident.

1. Anaesthetic Eye Drops

Before starting, your surgeon will apply numbing eye drops. These take effect quickly, and you won’t feel pain just a cool, slightly wet sensation.

Some clinics may also give you an oral sedative or mild anti-anxiety tablet to help you relax.

2. Eyelid Holder Placement

A small, sterile device keeps your eyelids gently open. It may feel unusual but not painful. You’ll still be able to blink naturally against it.

3. Epithelium Removal (Epi-Off Only)

If you’re having the epi-off version, the surface cells are carefully removed. You may feel slight pressure or a cool sensation but not pain, thanks to the anaesthetic.

4. Riboflavin (Vitamin B2) Application

The surgeon will apply riboflavin drops for 20–30 minutes. They may feel cool or a little sticky. During this time, your vision may appear slightly yellow due to the dye.

5. UV Light Activation

You’ll then look at a blue UV light for about 10–30 minutes. The light doesn’t burn or sting; you’ll mostly feel a sense of mild warmth or dryness.

You can relax the machine tracks your eye movements to ensure precision.

6. Protective Lens Placement

After the UV treatment, a soft bandage contact lens is placed on your eye. This acts like a cushion while the epithelium heals, significantly reducing discomfort during the first few days.

The entire procedure takes about 60–90 minutes from start to finish.

Immediately After Surgery: What You’ll Experience

Right after your corneal cross-linking procedure, your eye will likely:

• Feel gritty or watery
• Look red or slightly swollen
• Be sensitive to light

These sensations are normal and expected. Many patients describe the feeling as “having an eyelash stuck in the eye” or “mild irritation,” rather than true pain.

Your surgeon will provide protective glasses, antibiotic drops, and lubricating eye drops to prevent infection and ease dryness.

How Pain Is Managed During and After Treatment

1. During the Procedure

• Anaesthetic drops numb the eye completely.
• You won’t feel cutting or burning sensations.
• You may notice light pressure or slight dryness but not pain.

2. In the First 24–48 Hours

As the anaesthetic wears off, your eye’s surface begins to heal. This is when mild to moderate discomfort is most common. Symptoms may include:

• Grittiness
• Tearing
• Light sensitivity
• Blurred vision
• Stinging or mild ache

Your clinic will provide pain relief options, such as:

• Lubricating eye drops (to soothe dryness)
• Cold compresses
• Oral painkillers like paracetamol or ibuprofen
• Topical anti-inflammatory drops (as prescribed)

Avoid rubbing your eye the protective contact lens and lubricants will do their job.

Comparing Pain Levels: What Patients Say

Every patient’s pain threshold and healing speed differ, but most describe a very similar pattern of how the discomfort changes over time.

During the treatment itself, you’ll feel some gentle pressure but no pain at all many rate this at about 0 to 1 on a scale of 10.

In the first 6 to 12 hours after the procedure, mild burning, tearing, or stinging can appear as the anaesthetic wears off. Most patients rate this around 3 to 5 out of 10.

By day two or three, the surface healing process is underway, and the eye can feel gritty or slightly sore typically 4 to 6 out of 10 in terms of discomfort.

Around day four or five, the irritation tends to ease significantly as the corneal surface closes, bringing comfort levels down to about 2 to 3 out of 10.

From day six onwards, the vast majority of patients feel almost back to normal, with minimal or no discomfort.

Most people notice that any soreness peaks around the second day, then gradually improves with each passing day as healing continues.

Healing Timeline and Sensation Changes

Day 1–2:

You may experience tearing, blurry vision, and sensitivity to light. Sunglasses and resting your eyes help significantly.

Day 3–4:

Discomfort begins to subside. The corneal surface starts to re-epithelialise.

Day 5–7:

The protective contact lens is usually removed. By now, pain and irritation are minimal.

Week 2 and Beyond:

Your vision becomes clearer each week. Dryness and glare may linger temporarily but are easily managed with drops.

It’s rare for patients to need prescription painkillers simple over-the-counter medication is typically enough.

Factors That Influence Discomfort

Not everyone experiences corneal cross-linking in the same way. Several factors can affect comfort levels:

1. Procedure Type – Epi-off tends to cause more surface sensitivity; epi-on is gentler.
2. Individual Healing Speed – Some corneas regenerate faster than others.
3. Age – Younger patients often recover more quickly.
4. Dry Eye History – Pre-existing dryness may cause extra irritation.
5. Post-Op Care Compliance – Using prescribed drops and avoiding eye rubbing make a big difference.

Even with these variations, true pain is rare discomfort is the more accurate word.

Can You Work or Travel After Surgery?

You’ll need to rest your eyes for a few days after surgery. Most people return to work within a week, depending on their job and comfort level.

• Reading or screen work: Limit for the first 2–3 days.
• Driving: Wait until your specialist confirms your vision meets safety standards.
• Travel: Air travel is generally safe after a week if your eye is healing well.

Always follow your surgeon’s guidance rushing recovery can delay healing.

Tips for a Comfortable Recovery

Here’s how to make your recovery as smooth as possible:

1. Follow all eye drop instructions carefully. These prevent infection and inflammation.
2. Keep eyes closed or rest often. Short naps speed up healing.
3. Avoid rubbing or pressing your eye. It can disturb the healing surface.
4. Use sunglasses outdoors. They reduce glare and protect against UV exposure.
5. Stay hydrated. Adequate water helps tissue recovery.
6. Use cold compresses. These soothe discomfort and reduce swelling.
7. Avoid makeup and swimming. Wait at least two weeks before resuming.

Your eye will thank you for gentle care during this short but crucial phase.

Is There Pain After Both Eyes Are Treated?

Corneal cross-linking is usually done one eye at a time to ensure safe recovery and maintain clear vision in the untreated eye.

If both eyes are treated within a short gap, you may experience temporary difficulty focusing or reading but the overall discomfort remains manageable.

Surgeons often schedule the second eye once the first has healed comfortably.

Pain Relief Innovations in Modern Cross-Linking

Over the last decade, cross-linking techniques have become significantly more comfortable thanks to:

• Advanced riboflavin formulas that absorb faster, reducing total exposure time.
• Accelerated protocols that shorten UV light sessions to 10 minutes or less.
• Better contact lens materials that soothe the corneal surface post-surgery.
• Personalised light intensity adjustments based on corneal thickness, minimising irritation.

Modern CXL is a well-refined procedure and its discomfort profile is much lower than it was in the early 2000s.

When Pain May Indicate a Problem

While mild discomfort is normal, severe or prolonged pain is not. Contact your surgeon immediately if you experience:

• Sharp or increasing pain beyond day 4–5
• Thick discharge or excessive redness
• Sudden drop in vision
• Swelling around the eyelids

These may indicate infection or delayed healing, which are rare but treatable complications.

Prompt follow-up ensures the best recovery outcome.

Emotional Reassurance: Why Fear Is Common

Many patients admit that the idea of an “eye procedure” feels intimidating even if they’ve been told it’s minor.

It helps to remember:

• Your eye is completely numbed during surgery.
• The surgeon monitors you closely at every step.
• Recovery discomfort is temporary and manageable.
• Most people say it was “easier than expected.”

At Eye Clinic London, our specialists explain every detail before and after corneal cross-linking treatment so that you feel calm, confident, and informed from start to finish.

Common Myths About Pain and Corneal Cross-Linking

Myth 1: The UV light burns the eye.
False. The UV light is low-intensity and medically controlled it activates riboflavin, not the corneal tissue itself.

Myth 2: You’ll feel everything during surgery.
False. Anaesthetic drops completely numb your eye surface. You may feel gentle pressure, but no pain.

Myth 3: Pain lasts for weeks.
False. Most people are comfortable again within 5–7 days.

Myth 4: You’ll need strong painkillers.
False. Over-the-counter medication is usually sufficient.

Myth 5: Cross-linking is unbearable.
False. Discomfort is mild and temporary especially when proper aftercare is followed.

Why Temporary Discomfort Is Worth It

Although recovery can feel a little uncomfortable, the benefits of CXL far outweigh the short-term inconvenience.

Corneal cross-linking is the only proven treatment that stops the progression of keratoconus. Without it, the condition may worsen, leading to blurred vision, irregular astigmatism, and even the need for a corneal transplant.

By undergoing CXL, you’re investing in long-term visual stability and a few days of mild irritation is a small price for years of clear, stable vision.

Frequently Asked Questions About Corneal Cross-Linking

1. Will I be awake during corneal cross-linking?
   Yes, you’ll be awake throughout the procedure, but you won’t feel pain. Anaesthetic drops numb your eye completely, so you’ll only notice a bit of pressure or coolness. Many patients find that the anticipation feels worse than the actual experience. You’ll be able to relax, listen to your surgeon’s instructions, and rest comfortably during the short treatment.
2. How long does recovery really take?
   Most people feel back to normal within a week. The first few days can bring mild irritation, tearing, or light sensitivity, but these gradually fade. By the time your bandage lens is removed usually around day five the surface of your eye has largely healed. Your vision may take several weeks to fully stabilise, but daily comfort returns quickly.
3. Can I drive after the procedure?
   You shouldn’t drive immediately after your treatment or the next day, as your vision will be blurry and light-sensitive. Once your specialist confirms that your vision meets safety standards, usually within five to seven days, you can return to driving safely. Until then, arrange for someone to drive you home after the procedure.
4. Will I need to take time off work?
   That depends on the kind of work you do. If your job involves screen work or bright lighting, you may want to take about five days off to rest your eyes. For lighter tasks or jobs that don’t strain your vision, you might return sooner. Many people plan their treatment before a weekend or short break for convenience.
5. Can I wear contact lenses again after cross-linking?
   Yes, but only once your eye has fully healed. Your specialist will let you know when it’s safe to resume wearing them, usually after two to four weeks. It’s important not to rush this step putting contacts in too early can irritate the corneal surface and slow down recovery.
6. Will I still need glasses or lenses after the treatment?
   Corneal cross-linking doesn’t aim to remove the need for glasses or contact lenses. Instead, it stops your cornea from getting thinner and more irregular. Once the cornea stabilises, you may find that your vision prescription changes slightly. In some cases, new glasses or scleral lenses can improve clarity significantly.
7. Is the procedure safe for both eyes at once?
   It can be done, but most surgeons prefer treating one eye at a time. This allows you to rely on your untreated eye while the first one heals. If both eyes need treatment, your doctor might schedule the second procedure a few weeks later once you’re comfortable and your first eye has recovered.
8. What if I’m really anxious about the procedure?
   Feeling nervous is completely normal many patients share that fear before surgery. The good news is that your eye will be fully numb, and the team will explain every step as it happens. Some clinics even offer a mild sedative to help you relax. Remember, your comfort is a priority throughout the entire process.
9. How will I know if something’s wrong after surgery?
   It’s rare for complications to occur, but it’s important to stay alert. If you notice sharp pain, thick discharge, or worsening redness after four or five days, contact your surgeon straight away. These signs may indicate infection or delayed healing, both of which can be treated quickly when caught early.
10. Are the results permanent?
    Yes, in most cases they are. Corneal cross-linking creates permanent collagen bonds that strengthen your cornea for life. The treated eye usually remains stable for many years, though regular check-ups are essential. Your ophthalmologist will monitor your corneal shape and vision over time to ensure everything stays healthy.

Final Thoughts: Protecting Your Vision for the Long Term

If you’ve been diagnosed with keratoconus, undergoing corneal cross-linking treatment can make all the difference in preserving your vision and preventing further deterioration. The procedure might sound daunting at first, but most patients are pleasantly surprised by how manageable the recovery feels especially with modern anaesthetic techniques and careful aftercare.

Remember, the few days of mild discomfort after surgery are temporary, while the benefits of a stronger, more stable cornea can last a lifetime. Following your surgeon’s advice, using your prescribed eye drops, and attending all follow-up appointments will help ensure a smooth and successful healing process.

If you’re considering corneal cross-linking treatment in London, you can contact us at Eye Clinic London. Our specialists are dedicated to providing safe, effective, and patient-centred care guiding you through every step, from consultation to recovery, so you feel informed, supported, and confident about your vision’s future. Your eyesight deserves the best protection possible and with the right care, you can look forward to clear, stable vision for many years ahead.

References:

1. Raiskup, F., Theuring, A., Pillunat, L.E. and Spoerl, E., 2015. Corneal collagen crosslinking with riboflavin and ultraviolet-A light in keratoconus: long-term results. Journal of Cataract & Refractive Surgery, 41(1), pp.41–46. https://journals.lww.com/jcrs/abstract/2015/01000/corneal_collagen_crosslinking_with_riboflavin_and.8.aspx
2. van der Valk Bouman, E., Pels, E. & Ziaei, M., 2021. Pain mechanisms and management in corneal cross-linking: a review. BMJ Open Ophthalmology, 6(1), e000878. https://pubmed.ncbi.nlm.nih.gov/34901466/
3. Soeters, N., Godefrooij, D.A., Melles, G.R. & Wisse, R.P., 2020. Prospective 3-arm study on pain and epithelial healing after corneal cross-linking. Cornea, 39(7), pp.915-921. https://pubmed.ncbi.nlm.nih.gov/32050235/
4. Balparda, K., Alfaro, M., Rojas, C. & Salcedo, C., 2022. Complications of corneal collagen cross-linking. Indian Journal of Ophthalmology, 70(5), pp.1437-1449. https://pmc.ncbi.nlm.nih.gov/articles/PMC9333012/
5. Cifariello, F. et al., 2018. Epi-Off versus Epi-On corneal collagen cross-linking in keratoconus patients: a comparative study through 2-year follow-up. Journal of Ophthalmology, 2018:4947983. https://pmc.ncbi.nlm.nih.gov/articles/PMC6087595/