Red Light Therapy for Dry AMD: What the LIGHTSITE III Trial Actually Showed
Red Light Therapy for Dry AMD: The Short Version
Red light therapy for dry age-related macular degeneration (AMD) shines low-power colored light into the eye. Doctors call it photobiomodulation. The idea is to help the cells in the macula work better and slow the disease. It is not a laser and it does not burn tissue. One device, called Valeda, is now authorized for this use in the United States. This page explains what the main study, LIGHTSITE III, found.
In LIGHTSITE III, eyes treated with photobiomodulation gained about 6 letters of vision on a standard eye chart at 21 months, more than the sham (reduced-light) comparison group, and fewer treated eyes developed advanced dry AMD by 24 months.1 The gains were real but modest, and this was a single trial, so the results are promising rather than settled.
This page describes what researchers measured across a group of people. It cannot tell you how your own eyes would respond, because results varied from person to person, and many treated eyes did not gain much vision at all. Use it to ask your eye doctor better questions, not as a promise of what red light therapy would do for you.
What Photobiomodulation Is and Why Dry AMD Is Hard to Treat
Dry AMD is the more common form of AMD, blurs the sharp central vision you use to read and see faces, and can slowly advance to a late stage called geographic atrophy, where patches of the retina waste away.2 For years, the main tools for dry AMD were AREDS2 vitamins and monitoring, so a treatment aimed at the disease process itself is a genuine change.
Photobiomodulation delivers several wavelengths of low-level light, including 590, 660, and 850 nanometers, that are thought to boost energy production in retinal cells and reduce stress on them.1 The light is applied to the eye in short sessions. It is a proposed way to support struggling cells, not a way to replace cells that are already gone.
In November 2024, the FDA authorized marketing of the Valeda Light Delivery System to help improve vision in certain people with dry AMD.3 That authorization means the FDA reviewed the safety and effectiveness data and allowed the device to be marketed, which is an important step but not the same as calling it a cure.
What the LIGHTSITE III Trial Found
LIGHTSITE III was a randomized, double-masked, sham-controlled study in which 148 eyes from 100 people with dry AMD were assigned to either photobiomodulation or a sham light, with treatment series repeated every 4 months over 24 months.1 A design like this, where neither patients nor examiners know who got the real light, is meant to keep the comparison fair.
At 21 months, treated eyes gained on average about 6 letters of best-corrected vision compared with sham, and roughly 62 of every 100 treated eyes gained at least 5 letters, while about 23 of every 100 gained at least 10 letters.1 Five letters is about one line on an eye chart, so these are meaningful but not dramatic changes for most people.
By 24 months, new geographic atrophy appeared in about 7 of every 100 treated eyes, compared with about 24 of every 100 sham-treated eyes.1 This suggests the treatment may slow progression to advanced dry AMD, though it was measured in a fairly small group and needs confirming in larger studies.
In the trial, photobiomodulation was well tolerated, with few adverse events and no signs of light-related damage to the eye.1 A good short-term safety record is reassuring, but it reflects a limited number of people followed for two years, not decades of use.
How Strong Is the Evidence, Really?
The honest summary is that this rests largely on a single well-designed trial with modest average effects. The average vision gain over sham was a few letters, and many treated eyes did not gain much, so group averages hide a wide range of individual results.1 Promising early evidence is not the same as long-settled proof.
The comparison group in LIGHTSITE III received a reduced-strength light rather than no light at all, which the authors note may itself produce a small biological effect.1 If the sham was not completely inactive, the true difference between real treatment and doing nothing could be a little larger or smaller than the numbers suggest.
Several important questions remain open. We do not yet know whether the vision benefit lasts beyond two years, whether it holds up in much larger and more diverse groups, or how it compares with simply monitoring and taking AREDS2 vitamins. Longer, larger studies are needed before anyone can say how much this changes the long-term course of dry AMD.
Risks, Costs, and a Realistic Outlook
Treatment is given in a clinic as a series of short light sessions, typically several sessions over a few weeks that are repeated every few months, and in the trial it caused few side effects.1 The main downsides for most people are the time, the repeat visits, and the uncertainty about how much benefit they will personally get.
Because photobiomodulation for dry AMD is new, coverage and pricing are still uneven. Many vision and medical plans do not yet cover it, so it is often paid out of pocket, and availability depends on which clinics have the device. Ask the clinic for the total cost of a full course, and check directly with your own plan before you commit, rather than assuming it is covered.
For the right person, red light therapy may modestly help vision and may slow progression to advanced dry AMD, based on one two-year trial. It is not a cure, it will not restore vision that is already lost, and results vary widely between people. Think of it as one emerging option to discuss, weighed against its cost, time, and the limits of the current evidence.
When to See Your Eye Doctor
Some changes should not wait for a routine visit. A sudden drop in central vision, a new dark or blank spot, or straight lines that suddenly look wavy or bent can mean dry AMD has turned into wet AMD, which can worsen quickly.2 Call your eye doctor right away if this happens, because wet AMD can be treated, and acting early gives you the best chance to protect your central vision.
Steady monitoring matters even if your vision feels stable. Ask your eye doctor how often you need dilated eye exams and whether to check each eye at home for new distortion. Regular checks catch changes early, when there are usually the most options to act.
If you want to explore red light therapy, a retina specialist or an ophthalmologist who treats AMD is the right person to ask. They can confirm whether you have the type and stage of dry AMD studied in the trial, weigh it against your other care, and tell you whether the device is even available near you.
Common Questions About Red Light Therapy for AMD
No. It is not a cure, and it does not reverse dry AMD. In the LIGHTSITE III trial, treated eyes gained a few letters of vision on average and were less likely to progress to advanced dry AMD, but many eyes changed little.1 The goal is to support failing cells and slow the disease, not to restore normal vision.
The FDA took a formal step, but read it carefully. In November 2024 the FDA authorized marketing of the Valeda Light Delivery System to help improve vision in certain people with dry AMD.3 That means the agency reviewed the safety and effectiveness data and allowed marketing. It is meaningful, but it is not a guarantee of a large benefit for any one person.
Almost certainly not. Photobiomodulation is meant to help cells that are struggling but still alive, not to bring back retina that has already been lost to atrophy. Even in the trial, the average gain was only a few letters of vision, so it is best understood as protecting and modestly improving remaining sight, not recovering vision already gone.1
No, and this matters for safety. The trial used a specific medical device that delivers set wavelengths and doses under professional supervision. Consumer red-light panels, bulbs, and laser pointers are not the same, are not tested for the eye, and can be dangerous to look into. Never try to treat your own eyes with a household or hobby light source.
The trial studied dry AMD, not wet AMD. LIGHTSITE III enrolled people with dry (nonexudative) AMD, so its results do not apply to wet AMD, which is treated differently, usually with injections.1 If you have wet AMD, this is not the treatment being studied for you.
It is a repeating commitment, not a one-time fix. In the trial, people received a series of several light sessions over a few weeks, and that series was repeated every 4 months over 2 years.1 Ask your clinic exactly how many visits a full course would take, since the schedule affects both time and cost.
More Questions About Cost and Deciding
Often not, at least for now. Because the treatment is new, many medical and vision plans do not yet cover it, and people frequently pay out of pocket. Coverage and pricing vary by plan and clinic, so ask the clinic for the full cost of a course and confirm directly with your own plan before you start, rather than assuming it will be paid.
No, not on your own. Photobiomodulation is an add-on being studied alongside standard dry AMD care, not a replacement for it. Do not stop AREDS2 vitamins, monitoring, or any prescribed treatment without talking to your eye doctor first, and let them coordinate any new option so nothing important is dropped from your plan.
- Do I have the type and stage of dry AMD that was studied in LIGHTSITE III?
- Given my vision, how much benefit might I realistically expect, and how would we measure it?
- What is the full cost of a course, and will any part be covered by my plan?
- How many visits would treatment take, and for how long?
- How would this fit with my AREDS2 vitamins and the rest of my AMD care?
- Is the device available here, or would I need to travel?
- RETINA (open-access via PubMed Central, PMC13117590) (2025). Long-Term Efficacy and Safety of Photobiomodulation in Dry Age-Related Macular Degeneration (LIGHTSITE III: 24-Month Analysis).
- National Eye Institute (NEI), National Institutes of Health (2024). Age-Related Macular Degeneration.
- U.S. Food and Drug Administration (FDA) (2024). FDA Roundup: November 5, 2024 (Valeda Light Delivery System marketing authorization).