Keratoconus: Symptoms, Causes, Treatment and Integrative Support

Keratoconus is an eye condition in which the cornea, the clear dome at the front of the eye, thins and bulges forward into a cone^1,2. The uneven shape blurs and distorts vision, and glasses prescriptions often change quickly^3,2,4. It usually starts in the teenage years or twenties. It affects both eyes, often one more than the other^2,5,6. A Dutch insurance study estimated that about 1 in 375 people have it, and the average age at diagnosis was 28⁷. Keratoconus rarely causes blindness⁸. Glasses or specialist contact lenses give useful vision for most people^9,10. Corneal cross-linking, which uses riboflavin (vitamin B2) drops and ultraviolet light, is the only treatment shown to slow or stop it getting worse^11,12. It does not return the cornea to a normal shape, so keratoconus is managed rather than cured^13,12. Stopping eye rubbing and treating any eye allergy are part of that management².

This page explains what keratoconus is, its symptoms, and the emergency that needs same-day care. It covers what raises the risk, including whether it runs in families, and how keratoconus is diagnosed and monitored. It then sets out what treatment can do today: glasses and lenses, cross-linking, ring segments and other procedures, and corneal transplant. It answers whether keratoconus can be cured, lists what is in clinical trials, and ends with where integrative care can and cannot fit alongside your eye doctor.

Keratoconus at a glance

On this page

• What is keratoconus?
• Symptoms
• Causes and risk factors
• Diagnosis
• Treatment today
• Can keratoconus be cured?
• New treatments in clinical trials
• Living with keratoconus
• Where integrative care fits
• Outlook
• Frequently asked questions
• Sources

What is keratoconus?

The cornea is the clear, dome-shaped window at the front of the eye. It helps the eye focus light, so its shape matters a great deal for clear vision²⁴. In keratoconus the cornea thins and weakens, and the thinned area bulges forward into a cone^1,2,19. The surface becomes steeper and uneven. This causes nearsightedness and irregular astigmatism, an uneven curve that glasses cannot fully correct².

Keratoconus has traditionally been called non-inflammatory, and the eye usually does not look red^1,25. Researchers now think the immune system may also play a part: in a Dutch study, people with keratoconus were more likely than others to have several immune-related conditions²⁵. Our article on why inflammation matters in keratoconus looks at this research and at non-surgical care.

Keratoconus affects both eyes. A 2015 international consensus of cornea specialists concluded that true one-eyed keratoconus does not exist^26,27. The two eyes are often affected unequally. The largest US study to follow people with keratoconus over time is the Collaborative Longitudinal Evaluation of Keratoconus (CLEK). In CLEK, the worse eye was on average about 4 diopters steeper than the better eye; a diopter is the unit for how strongly the cornea bends light. One in five people (21%) had scarring in only one eye⁵.

It usually changes most in the teens and twenties and slows with age. In an analysis of 11,529 untreated eyes, steepening was faster in younger people and slowed with every decade of age²⁸. Experts describe keratoconus as usually stabilizing by the thirties or forties^2,15. There is no fixed age at which it stops, which is why regular scans continue into adulthood².

Symptoms of keratoconus

Early keratoconus can look like an ordinary need for glasses. Common symptoms include^2,3,15:

• blurred vision that glasses no longer fully correct;
• distorted vision, with straight lines looking bent or wavy;
• doubled or "ghost" images, even with one eye closed;
• glare, halos or starbursts around lights, which can make night driving hard;
• sensitivity to light;
• a glasses prescription that keeps changing, often with rising astigmatism.

Symptoms usually come on gradually, and each eye may be affected differently^3,15. In children and teenagers, a rising or changing astigmatism can be the first sign, and keratoconus is often already moderate or advanced when it is first found².

Keratoconus does not usually cause sudden pain, though many people with it report eye discomfort⁸. New or severe pain may mean a lens problem, an infection or the emergency described below, and needs prompt care².

Signs that need prompt care

See your eye doctor soon if your glasses no longer give clear vision, your prescription keeps changing, or one eye is falling behind the other^3,2.

Get same-day care for^3,2,29:

• sudden clouding or loss of vision in one eye, often with pain, watering and light sensitivity;
• a red, painful eye while wearing contact lenses. Take the lenses out and contact your eye doctor.

Acute hydrops: sudden clouding

In advanced keratoconus, a tear can open in the thin back layer of the cornea. Fluid floods in, and the cornea suddenly swells and turns cloudy^30,15. This is called acute corneal hydrops.

• How common: a UK national study estimated it affects at least 1.4 in every 1,000 people with keratoconus each year. Three in four were male, and half were younger than 32³¹.
• How it heals: the swelling usually settles on its own over weeks to months. In a Japanese series it cleared within three months in 71% of eyes³². Treatment includes drops to reduce swelling and protect the eye, and sometimes an injection of gas or air into the eye to speed healing^33,34.
• What it leaves behind: it often leaves a scar³⁰. In the UK study, a corneal transplant had been planned for 20% of patients within six months³¹.

Hydrops is more common with severe allergic eye disease, and in people with Down syndrome or developmental delay^35,36,37.

What causes keratoconus, and who is at risk?

The cause is not fully understood. Genes, eye rubbing and allergy all appear to play a part^1,16. All the links below come from observational studies, which show associations but cannot prove cause.

Eye rubbing. This is the most consistent link and the one you can change. In a worldwide review of studies, eye rubbing roughly tripled the odds of keratoconus¹⁶. In a Canadian study it was the only factor still linked to keratoconus after allowing for others³⁸. In a French study, rubbing with the knuckles carried a higher risk than rubbing with the fingertips³⁹. One review that combined 15 studies found no clear link, so the evidence is not unanimous⁴⁰. Cornea specialists nonetheless agree that controlling rubbing and allergy is the first step in care².

Family history. Keratoconus often runs in families. In one study, 3.3% of the parents, brothers, sisters and children of people with keratoconus had it, 15 to 67 times the rate in the general population⁴¹. When relatives' corneas are scanned, the share found to have it is higher, about 9% to 18% in different studies^42,43. In CLEK, 13.5% of people with keratoconus knew of an affected relative¹⁰.

Genes. The largest genetic study found 36 regions of DNA linked to keratoconus, many involved in the strength of the cornea's collagen⁴⁴. Together these common variants explain only part of the risk. Genetic tests are sold commercially, but European experts say they are not yet accurate enough to predict who will develop keratoconus^2,44.

Allergy, asthma and eczema. In the same worldwide review, allergy, asthma and eczema were each linked to higher odds of keratoconus¹⁶. The link may run through the itch-and-rub cycle³⁸. In CLEK, 53% of people with keratoconus reported a history of allergic disease¹⁰.

Down syndrome. Keratoconus is much more common in people with Down syndrome. A review that combined several studies put it at about 9%⁴⁵. A New Zealand study that examined 190 people with Down syndrome aged 10 and over found it in 26%³⁶.

Sleep apnea and floppy eyelids. In a review that combined five studies, obstructive sleep apnea was linked to almost twice the odds of keratoconus. Most of those studies used questionnaires rather than sleep tests¹⁸. Loose, floppy upper eyelids are also more common⁴⁶. If you snore, or wake unrefreshed, it is worth mentioning to your doctor¹⁷.

Ethnicity. In US insurance data, Black and Latino people were more likely to be diagnosed with keratoconus than white people, and Asian people less likely¹⁷. In the UK, keratoconus was about four times as common in people of South Asian origin as in white people⁴⁷.

Pregnancy. Small studies suggest keratoconus can progress during pregnancy, possibly because of hormonal changes^48,49. If you have keratoconus and plan a pregnancy, talk to your eye doctor about monitoring⁴⁸.

What is not confirmed. Some patient websites list Ehlers-Danlos syndrome, Marfan syndrome and mitral valve prolapse. Large US studies have not confirmed a link with connective tissue or mitral valve disease^10,17. Small studies of people with Ehlers-Danlos or Marfan syndrome found little or no keratoconus^50,51. Diabetes may lower the risk, but two reviews that combined studies found no clear link either way^17,52,53. There is no good evidence that contact lenses cause keratoconus¹⁴. In CLEK, though, lens wear was linked to scarring of the cornea⁵⁴.

How keratoconus is diagnosed

Keratoconus is diagnosed by an eye doctor, usually an ophthalmologist or an optometrist who specializes in the cornea or contact lenses.

Corneal tomography is the key test. A camera maps the shape and thickness of the whole cornea, front and back². Changes on the back surface often appear before the front, so tomography can find keratoconus earlier than older topography scans, which map only the front². Across 45 studies, these devices detected established keratoconus with high accuracy; very early or suspected cases are harder to call⁵⁵.

The doctor also measures your best-corrected vision, the sharpest you can see with glasses or lenses. They examine the cornea with a slit-lamp microscope. Signs of more advanced disease include a brown iron ring around the cone and fine stress lines in the cornea^2,1.

Staging. The ABCD system grades the front and back curvature, the thinnest point of the cornea and your best-corrected vision⁵⁶. The 2026 update of the international consensus on keratoconus uses it as the basis of its severity scale^57,2.

Judging progression. The main question is whether the cornea is getting worse. Under the 2026 consensus update, progression means a consistent change in at least two of these: steeper front curvature, steeper back curvature, a thinner cornea, or worse vision^57,2. This is measured by comparing scans over months. It usually decides whether cross-linking is needed².

Children and teenagers. Keratoconus usually progresses faster in young people²⁸. In a New Zealand study, 77% of eyes in people aged 18 or under showed measurable change on scans over about three years⁵⁸. For this reason European experts recommend cross-linking at diagnosis in children, without waiting for proof of progression². In the US, Epioxa is approved from age 13. Photrexa's safety and effectiveness have not been established under 14, so cross-linking younger children is off-label^23,13.

Screening family members. Because keratoconus runs in families, close relatives benefit from a corneal scan². A European expert consensus suggests checking children with a family history at around 8 to 13 years of age, while noting that scans under age 12 can give false alarms². In a study that scanned young relatives aged 6 to 18, 17.5% had keratoconus⁴³.

How often you are checked. After diagnosis, the same European consensus suggests scans every 3 months up to age 12, every 4 months from 12 to 20, every 6 months from 20 to 40, and yearly after 40. The gaps can be lengthened if scans show no change². Keep copies of your scans and take them to any new eye doctor.

Keratoconus treatment today

Treatment has two separate goals: clear vision and stopping progression². Glasses and lenses give clear vision but do not stop progression. Cross-linking stops progression but does not usually remove the need for glasses or lenses^12,13. Many people need both.

Our guide to keratoconus treatment options compares cross-linking, specialty lenses, ring segments and transplants stage by stage.

Glasses and contact lenses

• Glasses and soft lenses work in early keratoconus, while the cornea is only mildly irregular¹⁵.
• Rigid gas permeable (RGP) lenses float on a layer of tears and create a smooth new front surface for the eye. They often give much sharper vision than glasses, and they are the most common way vision is restored^59,6,60. In CLEK, 65% of people wore them, and most found them comfortable¹⁰.
• Hybrid lenses have a rigid center and a soft outer skirt for comfort. In a Belgian series they improved vision, but 38% of eyes stopped wearing them within six months, mostly for discomfort⁶¹.
• Scleral lenses are larger rigid lenses that vault over the cornea and rest on the white of the eye, with a pool of saline underneath. In a US series of eyes fitted successfully, vision improved from about 20/63 with glasses to about 20/25 with scleral lenses⁶². In a Belgian study of severe keratoconus, 40 of 51 eyes that would otherwise have needed a transplant did well with long-term scleral lens wear⁶³.

Specialist lenses need careful fitting and good hygiene. In the US scleral lens series, 9.6% of eyes had a complication, including infection in 0.6%⁶². Lenses do not treat or stop keratoconus^12,6. In a UK trial, 43% of young people using glasses or lenses alone progressed within 18 months¹².

Corneal cross-linking

Cross-linking strengthens the cornea. Riboflavin (vitamin B2) drops soak into the cornea, and ultraviolet A light then makes its collagen fibers bond together and stiffen¹³. In the standard "epi-off" method, the thin surface layer of the cornea is removed first so the riboflavin can soak in¹³.

The FDA approved the first cross-linking system in the US, Photrexa with the KXL System, for progressive keratoconus in April 2016^22,64. A second approval followed in July 2016 for corneal ectasia, a similar thinning and bulging, after LASIK or other refractive surgery²². The label says safety and effectiveness have not been established in children under 14¹³.

The evidence:

• In the US trials behind the approval, treated corneas flattened by about 1.4 to 1.7 diopters at one year¹³. The comparison group had a sham (pretend) treatment and steepened slightly before most were cross-linked after 3 to 6 months¹³. Across the 205 people with keratoconus in these trials, 5.6% of treated eyes steepened by 2 diopters or more²⁰.
• In an Australian trial of 100 eyes, untreated corneas steepened by 1.75 diopters over three years, while treated corneas flattened by about 1 diopter⁶⁵.
• In KERALINK, a UK trial of 60 young people aged 10 to 16, keratoconus progressed in 7% after cross-linking, against 43% with glasses or lenses alone, at 18 months¹².
• In the Netherlands, about 25% fewer corneal transplants were done in people under 50 in 2012 to 2014, after cross-linking became available, than in 2005 to 2007⁶⁶.
• In a 10-year German follow-up of 34 eyes, the treated corneas stayed flatter than before treatment⁶⁷.

A 2015 Cochrane review judged the evidence then available to be of very low quality, before the larger trials above were published⁶⁸.

Recovery from epi-off cross-linking is uncomfortable for a few days while the surface heals. A temporary haze in the cornea is common and usually fades within a year. In 1% to 2% of patients, some haze or scarring was still present at 12 months¹³. Severe complications such as infection were uncommon, under 1.3% of treated eyes in a review^69,70. In a Swiss series of 117 eyes, 2.8% had a small central scar, and keratoconus kept progressing despite cross-linking in 7.6%. Progression was more likely when the cornea was very steep to start with²¹. If keratoconus keeps progressing after cross-linking, your cornea specialist may discuss repeat cross-linking or other options^21,2. Our article on keratoconus that progresses after cross-linking covers that situation.

Faster "accelerated" epi-off cross-linking, using stronger light for a shorter time, is the most common method outside the US, but it is not FDA-approved². Studies comparing it with the standard method have reached different conclusions about how much it flattens the cornea^71,72. Epioxa, below, also uses stronger, pulsed light for a shorter time, with the surface layer left on²³.

Epithelium-on cross-linking (Epioxa)

On 17 October 2025 the FDA approved Epioxa, from Glaukos, the first cross-linking treatment in the US that leaves the surface layer of the cornea in place^22,73. The company announced the approval on 20 October 2025⁷³. It is approved for keratoconus in people aged 13 and over²³. Epioxa uses its own riboflavin drops, an ultraviolet light treatment of about 11 minutes, and goggles that supply extra oxygen to the eye²³. It has been available in the US since March 2026⁷⁴.

• Evidence: in two trials with 409 patients, treated corneas were about 1 diopter less steep than sham-treated corneas at 12 months²³. In the first trial, the benefit at 6 months was seen in patients under 29. Patients 29 and older did not improve in either the treated or the sham group²³. Both trials were funded by Glaukos⁷⁵. In October 2026 Glaukos reported that the flattening was maintained at three years in 38 treated eyes. That extension had no comparison group and is not yet published in a journal⁷⁶.
• Side effects: the most common, in the pooled label data, was red eye (31% of treated eyes). Rates varied widely between the two trials^23,77,75. Haze, light sensitivity, eye pain and irritation were also reported²³.
• How it compares: Epioxa has not been compared head to head with epi-off cross-linking. The average flattening seen in its trials was smaller than in the epi-off trials, but the patients differed^13,23. A 2021 Cochrane review of earlier epi-on methods found no clear difference from epi-off, but the evidence was very uncertain¹¹. European experts still prefer epi-off cross-linking for children and young people under 21, because epi-on methods have been less effective at halting progression in children².

Ask your cornea specialist which method suits your eye, your age and how fast your keratoconus is changing.

Ring segments and other procedures

• Intracorneal ring segments are small curved plastic inserts placed inside the cornea to flatten the cone. In the US, Intacs have been allowed for keratoconus since 2004 under a humanitarian device exemption, a limited FDA approval for rare conditions. It covers adults 21 and over who can no longer see well with lenses or glasses and whose only other option is a transplant⁷⁸. Case series show better vision and flatter corneas in selected eyes, but there are no randomized trials comparing rings with lenses^79,80. Rings reshape the cornea but are not shown to stop progression, so they are often combined with cross-linking⁷⁹.
• Other options for selected patients include surface laser treatment combined with cross-linking, and an implantable lens inside the eye once keratoconus is stable^81,82. For advanced disease, options include donor-tissue ring segments (CAIRS) and Bowman layer transplantation, which places a thin layer of donor tissue inside the cornea to flatten it^83,84. Most of the evidence for these comes from case series. Experts reserve them for people who cannot wear rigid lenses².

Corneal transplant

A corneal transplant is used when the cornea is scarred, or when lenses no longer give useful vision^1,2. In CLEK, 12% of people had a transplant in at least one eye over eight years, before cross-linking was available⁸⁵.

• Types: deep anterior lamellar keratoplasty (DALK) replaces the front layers and keeps your own inner layer. Penetrating keratoplasty (PK) replaces the full thickness of the cornea. A Cochrane review found similar vision with either, and fewer rejection episodes with DALK¹⁹.
• Results: in the Australian national registry, 89% of first transplants for keratoconus were still working after 10 years, and 49% after 20 years⁸⁶. Vision of 20/40 or better was recorded in 74% of grafts⁸⁶. Recovery is long, and many people still need glasses or contact lenses afterward^87,88,89.

Treating eye rubbing and allergy

Controlling eye allergy and stopping eye rubbing is the first step in caring for keratoconus². Allergy drops prescribed by your eye doctor and artificial tears help with the itch². These measures may lower the risk of progression. They are not considered enough to halt keratoconus that is already progressing, and they do not replace cross-linking². In a French study, most people who stopped rubbing stayed stable over about four years, although there was no comparison group⁹⁰.

Why LASIK is not an option

LASIK is not done in keratoconus, because it thins and weakens a cornea that is already weak^91,92,93,94. In selected eyes, a cornea specialist occasionally combines surface laser treatment with cross-linking^81,2. Undetected keratoconus is thought to be an important cause of corneal ectasia after LASIK, which is why surgeons scan the cornea before refractive surgery^95,96. Cross-linking is FDA-approved for ectasia after refractive surgery¹³.

Can keratoconus be cured?

No treatment returns a keratoconus cornea to a normal shape. What treatment can do is:

• Stop it getting worse. In trials and a Swiss case series, cross-linking stopped progression in about 9 in 10 treated eyes over the first one to two years^20,12,21. In children, rates of further change after cross-linking vary more². It is less likely to work when the cornea is already very steep, so experts favor treating early^21,28.
• Give clear vision. Glasses, specialist contact lenses and, when needed, surgery or a transplant restore useful vision for most people^9,10,86.
• Lower the risk. Stopping eye rubbing and treating allergy are recommended because both are linked to progression².

Keratoconus also tends to slow down on its own with age, often by the thirties or forties^2,28. Be wary of eye drops, supplements, exercises or devices sold online or over the counter as a cure. None has been shown to reverse or stop keratoconus.

New treatments for keratoconus in clinical trials

Several treatments are in clinical trials. None of these is approved in the US. Phase 1 and 2 trials are small early studies; phase 3 trials are the large final trials before approval. Status is as of 19 October 2026⁹⁷.

Treat claims that any of these is already available with caution.

Living with keratoconus

• Keep your scans. Regular corneal scans are how progression is caught early². Keep copies and take them to any new eye doctor.
• Break the rubbing habit. Treat itchy eyes early, and ask your doctor about allergy treatment². Eye rubbing can behave like a habit that is hard to break, so it helps to notice when and why you do it¹⁰⁰.
• Look after your lenses. Follow the cleaning and replacement schedule. If a lens makes your eye red or painful, take it out and contact your eye doctor²⁹.
• Driving. Glare and halos can make night driving hard³. In CLEK, about 78% of people saw 20/40 or better in both eyes with glasses or lenses¹⁰. Check your state's vision standard for driving.
• Pregnancy. Keratoconus can progress during pregnancy, so plan scans before and after⁴⁸.
• Family. Encourage brothers, sisters and children to have a corneal scan².
• Wellbeing. Keratoconus affects daily life more than its prevalence suggests: in CLEK, quality-of-life scores fell between those of people with intermediate and advanced macular degeneration⁸. People treated with cross-linking reported fewer limits on daily activities¹⁰¹.

Where integrative care fits

Netra Eye Institute is an acupuncture and Oriental medicine practice. Nothing we offer replaces cross-linking, specialist contact lenses or corneal surgery, and keratoconus care stays with your cornea specialist. Our role is adjunctive: care that sits alongside your specialist's treatment, with the evidence explained before you start.

We found no published clinical trials of acupuncture, Chinese herbal medicine or Ayurveda in keratoconus. The part of keratoconus care where integrative support may fit is the itch-and-rub cycle that keratoconus experts single out². Whether acupuncture or herbs reduce eye itching or rubbing has not been tested. Acupuncture has some evidence, modest and uncertain, for hay fever symptoms^102,103. It has not been studied specifically for itchy eyes, eye rubbing or keratoconus.

Evidence grades describe how sure we can be about the effect on keratoconus. None means no studies; very low means small studies without proper comparison groups; low means consistent observational studies or weak trials.

What working with Netra looks like. We ask first that a cornea specialist or optometrist has made the diagnosis and set a plan for scans and cross-linking. If your vision changes suddenly, or your eye becomes red and painful, see them first; that comes before anything we do. Then we:

• check that the basics are in place: regular corneal scans, a plan for cross-linking if scans show progression, and allergy treatment;
• support your efforts to stop rubbing with habit coaching and, if you choose, acupuncture, which has not been tested for this;
• where appropriate, offer Chinese herbal medicine reviewed against your medicines;
• ask about snoring and sleep, and suggest a sleep assessment with your physician where it fits;
• never put herbal washes or drops in the eye, and wait for your surgeon's approval before any treatment near the eyes after cross-linking or a transplant;
• share what we see with your eye doctor, and refer back quickly if your vision changes or your eye becomes red or painful.

Netra Restoration Therapy (NRT) is an adjunctive program: it is used only alongside your cornea specialist's care, never instead of it. It is not a treatment for keratoconus. It does not replace cross-linking, specialist lenses or corneal surgery, and it does not reverse thinning or flatten the cone. No clinical trial of NRT in keratoconus has been published. For Ayurvedic approaches, see Ayurvedic treatment for keratoconus.

Outlook

Most people with keratoconus keep useful vision. In CLEK, 78% of people saw 20/40 or better in both eyes with their best correction¹⁰. Keratoconus rarely causes blindness. In a study of more than 27,000 keratoconus eyes in India, the few eyes with no light perception had lost it from other conditions, not from keratoconus itself^109,8.

Cross-linking has changed the outlook for young people, because it stops progression before much vision is lost^12,66. Without treatment, younger people and those with steeper corneas are most at risk of progression²⁸. The main things you can do are to keep your scans, stop rubbing, treat allergy, and act quickly if your scans show change.

Frequently asked questions

Is keratoconus genetic?

Partly. It often runs in families: 3.3% of close relatives of people with keratoconus had it in one study, 15 to 67 times the usual rate⁴¹. More than 30 gene regions have been linked to it⁴⁴. Genetic tests are sold, but experts say they are not yet accurate enough to predict who will develop it². Close relatives, especially children and teenagers, should have a corneal scan².

Can keratoconus be cured?

No treatment returns the cornea to normal. Cross-linking stopped progression in about 9 in 10 treated eyes over the first one to two years in studies, and lenses or surgery restore useful vision for most people^20,12,10,86.

Can keratoconus cause blindness?

Rarely. Keratoconus affects the cornea, not the nerve of the eye, and vision can usually be restored with lenses or a transplant^8,109. Sudden clouding from hydrops needs same-day care^2,15.

How fast does keratoconus progress, and when does it stop?

It progresses fastest in children and teenagers and usually slows by the thirties or forties^28,2. There is no fixed age at which it stops, so scans continue into adulthood².

Is there a treatment for keratoconus without surgery?

Glasses and contact lenses are non-surgical and give useful vision for most people^9,10. Cross-linking is an in-office procedure; Epioxa leaves the surface layer of the cornea in place²³. Our article on why inflammation matters in keratoconus also covers non-surgical care.

Can eye drops or supplements treat keratoconus?

No drop or supplement has been shown in a proper trial to stop or reverse keratoconus. Copper eye drops and other drops are in early trials⁹⁷. Cross-linking uses riboflavin drops, but only with ultraviolet light in the clinic¹³.

Can I have LASIK if I have keratoconus?

No. LASIK weakens the cornea and can make keratoconus worse^91,92,94. Some people with stable keratoconus are suitable for other procedures, such as an implantable lens^82,2.

Is cross-linking painful, and how long is recovery?

After epi-off cross-linking, the eye is usually sore for a few days while the surface heals, and vision can be hazy for weeks to months¹³. Epithelium-on treatment avoids removing the surface layer²³.

Is keratoconus painful?

It does not usually cause sudden pain, though many people with it report eye discomfort⁸. New or severe pain may mean a lens problem, an infection or hydrops, and needs prompt care².

Should my children be checked?

Yes, if a parent has keratoconus. European experts suggest checking at about 8 to 13 years². Children with high or changing astigmatism should also be scanned².

Can acupuncture or herbs help keratoconus?

There are no clinical trials of acupuncture, Chinese herbal medicine or Ayurveda in keratoconus, and none has been shown to change the cornea. Acupuncture has modest, uncertain evidence for hay fever symptoms^102,103. Netra offers it only as adjunctive care alongside your cornea specialist, with the evidence explained.

Sources

1. Rabinowitz YS. Keratoconus. Surv Ophthalmol. 1998. link
2. Buzzonetti L, et al. Paediatric keratoconus: an ERN-EYE clinical consensus statement on diagnosis, treatment and follow-up care. Ophthalmol Ther. 2026. link
3. Cleveland Clinic. Keratoconus. Updated September 22, 2026. link
4. U.S. Food and Drug Administration. LASIK: Glossary. July 11, 2018. link
5. Zadnik K, et al. Between-eye asymmetry in keratoconus. Cornea. 2002. link
6. Şengör T, Aydın Kurna S. Update on Contact Lens Treatment of Keratoconus. Turk J Ophthalmol. 2020. link
7. Godefrooij DA, et al. Age-specific incidence and prevalence of keratoconus: a nationwide registration study. Am J Ophthalmol. 2017. link
8. Kymes SM, et al. Quality of life in keratoconus. Am J Ophthalmol. 2004. link
9. National Eye Institute. Corneal Dystrophies. Updated December 6, 2024. link
10. Zadnik K, et al. Baseline findings in the Collaborative Longitudinal Evaluation of Keratoconus (CLEK) Study. Invest Ophthalmol Vis Sci. 1998. link
11. Ng SM, et al. Transepithelial versus epithelium-off corneal crosslinking for progressive keratoconus. Cochrane Database Syst Rev. 2021. link
12. Larkin DFP, et al. Effect of corneal cross-linking versus standard care on keratoconus progression in young patients: the KERALINK randomized controlled trial. Ophthalmology. 2021. link
13. Glaukos (Avedro). PHOTREXA VISCOUS and PHOTREXA (riboflavin 5'-phosphate ophthalmic solution) prescribing information. Revised February 2025 (DailyMed version effective July 24, 2026). link
14. Chan E, et al. Prevalence of keratoconus based on Scheimpflug imaging: the Raine Study. Ophthalmology. 2021. link
15. American Optometric Association. Keratoconus. link
16. Hashemi H, et al. The prevalence and risk factors for keratoconus: a systematic review and meta-analysis. Cornea. 2020. link
17. Woodward MA, et al. The association between sociodemographic factors, common systemic diseases, and keratoconus: an analysis of a nationwide heath care claims database. Ophthalmology. 2016. link
18. Pellegrini M, et al. Obstructive sleep apnea and keratoconus: a systematic review and meta-analysis. Optom Vis Sci. 2020. link
19. Keane M, et al. Deep anterior lamellar keratoplasty versus penetrating keratoplasty for treating keratoconus. Cochrane Database Syst Rev. 2014. link
20. Hersh PS, et al. United States multicenter clinical trial of corneal collagen crosslinking for keratoconus treatment. Ophthalmology. 2017. link
21. Koller T, et al. Complication and failure rates after corneal crosslinking. J Cataract Refract Surg. 2009. link
22. U.S. Food and Drug Administration. Drugs@FDA approval records for Photrexa (NDA 203324) and Epioxa (NDA 219910). Checked October 19, 2026. Photrexa · Epioxa
23. Glaukos (Avedro). EPIOXA HD and EPIOXA (riboflavin 5'-phosphate ophthalmic solution) prescribing information. October 2025. link
24. National Eye Institute. Corneal Conditions. Updated August 6, 2025. link
25. Claessens JLJ, et al. Nationwide epidemiological approach to identify associations between keratoconus and immune-mediated diseases. Br J Ophthalmol. 2022. link
26. Gomes JA, et al. Global consensus on keratoconus and ectatic diseases. Cornea. 2015. link
27. Ferraro V, et al. Outcomes of iontophoresis cross-linking in asymmetric keratoconus: a retrospective analysis of high visual acuity eyes. Clin Ophthalmol. 2024. link
28. Ferdi AC, et al. Keratoconus natural progression: a systematic review and meta-analysis of 11 529 eyes. Ophthalmology. 2019. link
29. Centers for Disease Control and Prevention. Preventing Eye Infections When Wearing Contacts. May 27, 2025. link
30. Fan Gaskin JC, et al. Acute corneal hydrops in keratoconus — new perspectives. Am J Ophthalmol. 2014. link
31. Barsam A, et al. Acute corneal hydrops in keratoconus: a national prospective study of incidence and management. Eye (Lond). 2015. link
32. Aichi T, et al. Identification of risk factors for persistent corneal edema associated with acute corneal hydrops in keratoconus. Jpn J Ophthalmol. 2025. link
33. Bafna RK, et al. Management of acute corneal hydrops — current perspectives. Indian J Ophthalmol. 2024. link
34. Basu S, et al. Intracameral perfluoropropane gas in the treatment of acute corneal hydrops. Ophthalmology. 2011. link
35. Tuft SJ, et al. Acute corneal hydrops in keratoconus. Ophthalmology. 1994. link
36. Mathan JJ, et al. Keratoconus in Down syndrome: prevalence, risk factors, severity and corneal tomographic characteristics. Clin Exp Ophthalmol. 2024. link
37. Kanu LN, et al. Sociodemographic predictors of acute corneal hydrops in patients with unstable keratoconus. PLoS One. 2025. link
38. Bawazeer AM, et al. Atopy and keratoconus: a multivariate analysis. Br J Ophthalmol. 2000. link
39. Moran S, et al. A case-control study of keratoconus risk factors. Cornea. 2020. link
40. Seth I, et al. The association between keratoconus and allergic eye diseases: a systematic review and meta-analysis. Clin Exp Ophthalmol. 2022. link
41. Wang Y, et al. Genetic epidemiological study of keratoconus: evidence for major gene determination. Am J Med Genet. 2000. link
42. Lapeyre G, et al. Keratoconus prevalence in families: a French study. Cornea. 2020. link
43. Awwad ST, et al. Tomographic and refractive characteristics of pediatric first-degree relatives of keratoconus patients. Am J Ophthalmol. 2019. link
44. Hardcastle AJ, et al. A multi-ethnic genome-wide association study implicates collagen matrix integrity and cell differentiation pathways in keratoconus. Commun Biol. 2021. link
45. Beresford-Webb JA, et al. The ocular manifestations of individuals with Down syndrome: a systematic review and meta-analysis. J Ophthalmol. 2025. link
46. Naderan M, et al. Prevalence of eyelid laxity and its association with ophthalmic findings and disease severity in patients with keratoconus. Eur J Ophthalmol. 2017. link
47. Pearson AR, et al. Does ethnic origin influence the incidence or severity of keratoconus? Eye (Lond). 2000. link
48. Naderan M, Jahanrad A. Topographic, tomographic and biomechanical corneal changes during pregnancy in patients with keratoconus: a cohort study. Acta Ophthalmol. 2017. link
49. Ashraf M, et al. Hormonal modulation of keratoconus: a systematic review and screening strategy for at-risk populations. Ophthalmol Sci. 2026. link
50. McDermott ML, et al. Corneal topography in Ehlers-Danlos syndrome. J Cataract Refract Surg. 1998. link
51. Konradsen TR, et al. Corneal curvature, pachymetry, and endothelial cell density in Marfan syndrome. Acta Ophthalmol. 2012. link
52. Dong XX, et al. Diabetes mellitus and keratoconus: a systematic review and meta-analysis. Cornea. 2022. link
53. Akowuah PK, et al. Association between diabetes and keratoconus — a systematic review and meta-analysis. Eur J Ophthalmol. 2022. link
54. Barr JT, et al. Estimation of the incidence and factors predictive of corneal scarring in the CLEK Study. Cornea. 2006. link
55. Kuo AN, et al. Advanced corneal imaging in keratoconus: a report by the American Academy of Ophthalmology. Ophthalmology. 2024. link
56. Belin MW, Duncan JK. Keratoconus: the ABCD grading system. Klin Monbl Augenheilkd. 2016. link
57. Gomes JAP, et al. Global Consensus on Keratoconus and Ectatic Diseases—Edition 2. Cornea. 2026. link
58. Meyer JJ, et al. Progression of keratoconus in children and adolescents. Br J Ophthalmol. 2023. link
59. Ortiz-Toquero S, et al. Clinical guidelines for the management of keratoconus patients with gas permeable contact lenses based on expert consensus and available evidence. Curr Opin Ophthalmol. 2021. link
60. Lim L, Lim EWL. Current perspectives in the management of keratoconus with contact lenses. Eye (Lond). 2020. link
61. Kloeck D, et al. Clinical outcome of hybrid contact lenses in keratoconus. Eye Contact Lens. 2021. link
62. Fuller DG, Wang Y. Safety and efficacy of scleral lenses for keratoconus. Optom Vis Sci. 2020. link
63. Koppen C, et al. Scleral lenses reduce the need for corneal transplants in severe keratoconus. Am J Ophthalmol. 2018. link
64. Avedro. Avedro Receives FDA Approval for Photrexa Viscous, Photrexa and the KXL System for Corneal Cross-Linking (press release). April 18, 2016. link
65. Wittig-Silva C, et al. A randomized, controlled trial of corneal collagen cross-linking in progressive keratoconus: three-year results. Ophthalmology. 2014. link
66. Godefrooij DA, et al. Nationwide reduction in the number of corneal transplantations for keratoconus following the implementation of cross-linking. Acta Ophthalmol. 2016. link
67. Raiskup F, et al. Corneal collagen crosslinking with riboflavin and ultraviolet-A light in progressive keratoconus: ten-year results. J Cataract Refract Surg. 2015. link
68. Sykakis E, et al. Corneal collagen cross-linking for treating keratoconus. Cochrane Database Syst Rev. 2015. link
69. Serrao S, et al. Adverse events after riboflavin/UV-A corneal cross-linking: a literature review. Int Ophthalmol. 2022. link
70. Murchison CE, et al. Infectious keratitis after corneal crosslinking: systematic review. J Cataract Refract Surg. 2021. link
71. Kobashi H, Tsubota K. Accelerated versus standard corneal cross-linking for progressive keratoconus: a meta-analysis of randomized controlled trials. Cornea. 2020. link
72. Yeh CY, et al. Accelerated versus conventional corneal collagen cross-linking for keratoconus: a meta-analysis of randomized controlled trials. Eur J Ophthalmol. 2025. link
73. Glaukos. Glaukos Announces FDA Approval of Epioxa (press release). October 20, 2025. link
74. Glaukos. Investor presentation, August 2026 (SEC Form 8-K exhibit 99.1). link
75. Beckman KA, et al. Randomized, controlled study to evaluate the safety and efficacy of oxygen-enriched epithelium-on corneal cross-linking for the treatment of keratoconus. Ophthalmol Ther. 2026. link
76. Ophthalmology Times. Glaukos' Epioxa maintains corneal flattening and visual gains through 3 years in keratoconus. October 8, 2026. link
77. ClinicalTrials.gov record NCT03442751 (epithelium-on cross-linking, phase 3, results posted January 30, 2024). Checked October 19, 2026. NCT03442751
78. U.S. Food and Drug Administration. Humanitarian Device Exemption H040002: INTACS Prescription Inserts for Keratoconus. Approved July 26, 2004. link
79. Benoist d'Azy C, et al. Efficacy of different procedures of intra-corneal ring segment implantation in keratoconus: a systematic review and meta-analysis. Transl Vis Sci Technol. 2019. link
80. Zadnik K, et al. Intrastromal corneal ring segments for treating keratoconus. Cochrane Database Syst Rev. 2019. link
81. Kanellopoulos AJ. Ten-year outcomes of progressive keratoconus management with the Athens protocol (topography-guided partial-refraction PRK combined with CXL). J Refract Surg. 2019. link
82. Alkhabbaz AA, et al. Safety and efficacy of posterior chamber phakic implantable collamer lenses in patients with keratoconus: a systematic review and meta-analysis. Am J Ophthalmol. 2025. link
83. Friedrich M, et al. Visual and topographic outcomes after corneal allogeneic intrastromal ring segments for keratoconus: a systematic review and meta-analysis. Am J Ophthalmol. 2025. link
84. De Clerck EEB, et al. Bowman layer transplantation for treating keratoconus — preliminary findings. J Clin Med. 2023. link
85. Gordon MO, et al. Baseline factors predictive of incident penetrating keratoplasty in keratoconus. Am J Ophthalmol. 2006. link
86. Kelly TL, et al. Corneal transplantation for keratoconus: a registry study. Arch Ophthalmol. 2011. link
87. National Eye Institute. Corneal Transplants. Updated September 4, 2025. link
88. Silbiger JS, et al. The rate of visual recovery after penetrating keratoplasty for keratoconus. CLAO J. 1996. link
89. Lim L, et al. Penetrating keratoplasty for keratoconus: visual outcome and success. Ophthalmology. 2000. link
90. Mazharian A, et al. Medium to long term follow up study of the efficacy of cessation of eye-rubbing to halt progression of keratoconus. Front Med (Lausanne). 2023. link
91. U.S. Food and Drug Administration. When is LASIK not for me? July 11, 2018. link
92. Colin J, Velou S. Current surgical options for keratoconus. J Cataract Refract Surg. 2003. link
93. Carl Zeiss Meditec. MEL 90 excimer laser patient information booklet for LASIK (FDA premarket approval P060004/S006, approved December 4, 2024). link
94. Alcon. WaveLight EX500 patient information booklet for INNOVEYES LASIK (FDA premarket approval P020050/S043, approved March 5, 2025). link
95. Randleman JB, et al. Validation of the Ectasia Risk Score System for preoperative laser in situ keratomileusis screening. Am J Ophthalmol. 2008. link
96. Moshirfar M, et al. Ectasia after corneal refractive surgery: a systematic review. Ophthalmol Ther. 2021. link
97. ClinicalTrials.gov records NCT06100939, NCT06100952, NCT07400952, NCT05241145, NCT05314738 and NCT07388069. Checked October 19, 2026. NCT06100939 · NCT06100952 · NCT07400952 · NCT05241145 · NCT05314738 · NCT07388069
98. Ophthalmology Management. Epion Completes Phase 3 Program for EpiSmart in Keratoconus. June 16, 2026. link
99. iVeena Delivery Systems. Glaukos Licenses iVeena's Investigational Keratoconus Therapy (press release). August 24, 2022. link
100. Hage A, et al. EYERUBBICS: the eye rubbing cycle study. J Clin Med. 2023. link
101. Kandel H, et al. Cross-linking improves the quality of life of people with keratoconus: a cross-sectional and longitudinal study from the Save Sight Keratoconus Registry. Cornea. 2023. link
102. Brinkhaus B, et al. Acupuncture in patients with seasonal allergic rhinitis: a randomized trial. Ann Intern Med. 2013. link
103. He M, et al. Acupuncture for allergic rhinitis: a systematic review and meta-analysis. Eur J Med Res. 2022. link
104. Peris-Martínez C, et al. Antioxidant and anti-inflammatory effects of oral supplementation with a highly-concentrated docosahexaenoic acid (DHA) triglyceride in patients with keratoconus: a randomized controlled preliminary study. Nutrients. 2023. link
105. Gupta PC, et al. Association of keratoconus with serum levels of 25-hydroxyvitamin D and antioxidant trace elements: a systematic review and meta-analysis. Indian J Ophthalmol. 2022. link
106. Lasagni Vitar RM, et al. Vitamin D supplementation impacts systemic biomarkers of collagen degradation and copper metabolism in patients with keratoconus. Transl Vis Sci Technol. 2022. link
107. Campêlo ESR, et al. Oral riboflavin supplementation and sunlight exposure: a possible novel and accessible approach to stabilize progressive keratoconus. Eur J Ophthalmol. 2026. link
108. Torres-Netto EA, et al. Oral riboflavin for sunlight-induced corneal cross-linking: efficacy assessment in a rabbit model in vivo using extensometry and OCT elastography. J Refract Surg. 2026. link
109. Deshmukh R, et al. Blinding associations of keratoconus (letter). Indian J Ophthalmol. 2023. link