Anti-VEGF Injections: Protecting Your Retinal Vision
Understanding Anti-VEGF Therapy
VEGF stands for vascular endothelial growth factor. It is a protein your body produces naturally to help grow new blood vessels when and where they are needed. In some eye conditions, cells in the retina produce too much VEGF. This excess VEGF causes abnormal blood vessels to grow inside the eye.
These abnormal blood vessels are fragile. They leak fluid and blood into the retina, which is the thin layer of tissue at the back of the eye responsible for converting light into the signals your brain reads as vision. When fluid and blood collect in or under the retina, central vision becomes blurry, distorted, or blocked.
Anti-VEGF medications are designed to bind to the VEGF protein and block it from triggering abnormal blood vessel growth. By neutralizing excess VEGF, these drugs reduce leakage from abnormal vessels and help prevent new ones from forming. This slows or stops damage to the retina and helps protect remaining vision.
The medication is delivered through an intravitreal injection, which means it is placed directly into the vitreous (the gel-like substance that fills the inside of the eye). Placing the drug inside the eye allows it to reach the retina at a much higher concentration than oral medication or eye drops could achieve.
Anti-VEGF therapy is used to treat several retinal conditions driven by abnormal VEGF activity. These include:
- Wet (neovascular) age-related macular degeneration
- Diabetic macular edema (swelling in the center of the retina caused by diabetes)
- Diabetic retinopathy (damage to retinal blood vessels from diabetes)
- Macular edema following retinal vein occlusion (a blockage in the veins that drain the retina)
- Myopic choroidal neovascularization (abnormal vessel growth related to severe nearsightedness)
Who Is Affected and Risk Factors
An estimated 20 million Americans have some form of age-related macular degeneration, and wet AMD is responsible for 90 percent of all AMD-related vision loss that leads to legal blindness (AAO, 2023). Wet AMD primarily affects people over age 50. Risk factors include smoking, family history of AMD, cardiovascular disease, and high blood pressure.
Approximately one-third of all people with diabetes have some form of diabetic retinopathy, with over 100 million cases worldwide. By 2045, the number of people with diabetic retinopathy is expected to increase by more than 50 percent (PMC, 2023). Among those with diabetic retinopathy, about one-third have a vision-threatening form of the disease. Uncontrolled blood sugar, high blood pressure, and longer duration of diabetes all raise the risk of needing anti-VEGF treatment.
Retinal vein occlusion is more common in people with high blood pressure, diabetes, and glaucoma. Myopic choroidal neovascularization can occur in younger adults with severe nearsightedness. In general, conditions that stress blood vessels throughout the body, such as smoking, obesity, and cardiovascular disease, also increase the risk of retinal conditions that may require anti-VEGF therapy.
Available Anti-VEGF Medications
Several anti-VEGF drugs are currently available for retinal treatment. Each works by blocking VEGF, but they differ in molecular design, approved uses, and how long they last in the eye.
- Lucentis (ranibizumab): The first anti-VEGF medication approved specifically for use in the eye. It is FDA-approved for wet AMD, diabetic retinopathy, diabetic macular edema, retinal vein occlusion, and myopic choroidal neovascularization. It is typically given every four weeks.
- Eylea (aflibercept): One of the most commonly used anti-VEGF agents. It is FDA-approved for wet AMD, diabetic macular edema, diabetic retinopathy, and retinal vein occlusion. After an initial series of monthly injections, dosing may extend to every four to eight weeks.
- Eylea HD (high-dose aflibercept): Approved in 2023, this is a higher-dose formulation of aflibercept designed for longer intervals between injections. After initial monthly doses, some patients may go eight to sixteen weeks between treatments.
- Vabysmo (faricimab): Approved in January 2022, Vabysmo is a bispecific antibody, meaning it targets two proteins: VEGF-A and angiopoietin-2. It is FDA-approved for wet AMD and diabetic macular edema. About half of patients in clinical trials were able to extend their treatment interval to four months.
- Beovu (brolucizumab): Approved for wet AMD with dosing intervals of eight to twelve weeks after initial monthly loading doses. Retina specialists may monitor for a rare risk of retinal vasculitis (inflammation of blood vessels inside the eye) with this medication.
Avastin (bevacizumab) was originally developed and FDA-approved to treat certain types of cancer. It is not FDA-approved for use in the eye. However, it is widely used off-label by retina specialists throughout the world to treat wet AMD, diabetic macular edema, and retinal vein occlusion. Large clinical trials, including the CATT study, showed that Avastin produces visual outcomes comparable to Lucentis for wet AMD. It is typically given every four to six weeks. Your retina specialist can discuss whether Avastin is appropriate for your condition.
Biosimilars are medications that are highly similar to an already approved biologic drug. Two biosimilars of Lucentis (ranibizumab) have been approved in the United States: Byooviz (ranibizumab-nuna), approved in September 2021, and Cimerli (ranibizumab-eqrn). These biosimilars are approved for the same eye conditions as Lucentis and offer additional options for retina specialists and patients.
What to Expect During Treatment
Before your first injection, a retina specialist will perform a thorough eye examination. This usually includes optical coherence tomography, or OCT (a scan that produces detailed cross-section images of the retina), and sometimes fluorescein angiography (a test using dye and a special camera to photograph blood flow in the retina). These tests help confirm the diagnosis and guide treatment decisions.
On the day of the injection, the eye is numbed with anesthetic drops or a small injection of numbing medicine around the eye. The surface of the eye is cleaned with an antiseptic solution to reduce the risk of infection.
The actual injection takes only a few seconds. A very fine needle is used to place a small amount of medication through the white part of the eye and into the vitreous cavity. Most patients feel pressure rather than sharp pain, though some discomfort is normal. You typically do not see the needle during the procedure. The retina specialist may check your eye briefly after the injection to confirm everything looks normal.
Mild redness, irritation, or a gritty feeling in the eye is common for a day or two. Some patients notice small floaters or a bubble in their vision, which usually clears within a few days. Your retina specialist will give you instructions about using any prescribed eye drops and will let you know when to return for your next visit.
Anti-VEGF treatment typically begins with a loading phase of monthly injections for the first three months. After that, the schedule depends on how the eye responds. Many retina specialists use a treat-and-extend approach, gradually lengthening the time between injections as long as the retina remains stable. Some patients eventually go two, three, or even four months between treatments. Others need injections more frequently to maintain control of their condition.
Anti-VEGF therapy is usually an ongoing treatment. Data from a large study of over 254,655 eyes with wet AMD showed that about 38.8 percent of eyes discontinued treatment during follow-up, and 32.3 percent switched to a different anti-VEGF agent at some point (IRIS Registry, PMC, 2024). Sticking with your recommended schedule is one of the most important things you can do to protect your vision.
Results and Effectiveness
Anti-VEGF treatment improves vision in about one out of three people who receive it. For the vast majority, roughly nine out of ten, it stabilizes vision and prevents further decline. Before anti-VEGF therapy became available in 2005, most people with wet AMD experienced progressive central vision loss. Today, patients have a much better chance of maintaining the central vision they need to read, drive, recognize faces, and carry out daily activities.
The benefits of anti-VEGF therapy depend on receiving injections on schedule. Missing appointments or stopping treatment early can allow the disease to become active again. Fluid and blood may return to the retina, and vision gains can be lost. If you are having difficulty keeping up with your treatment schedule, talk with your retina specialist about options. Newer medications with longer-lasting effects, such as Eylea HD (high-dose aflibercept) and Vabysmo (faricimab), may allow for fewer visits while still controlling the disease.
Living with Anti-VEGF Treatment
Between appointments, you can monitor your own vision using an Amsler grid. This is a simple chart with a grid of straight lines and a central dot. By looking at the grid one eye at a time, you can detect changes in your central vision, such as wavy lines, missing areas, or dark spots. Your retina specialist can provide an Amsler grid and instructions on how to use it.
Receiving ongoing eye injections can feel overwhelming. It is normal to feel anxious about the procedure, especially at first. Many patients find that the anticipation is more uncomfortable than the injection itself. If anxiety is a concern, let your retina specialist know. They may be able to offer additional numbing or other strategies to improve your comfort.
Living with a chronic retinal condition also means adjusting to regular medical visits. Planning ahead, arranging transportation, and keeping a calendar of appointments can help make the routine more manageable over time.
While anti-VEGF injections treat the disease directly, certain lifestyle choices support overall eye and vascular health. These include:
- Not smoking, as smoking significantly increases the risk of AMD progression
- Managing blood sugar carefully if you have diabetes
- Controlling blood pressure and cholesterol
- Eating a balanced diet rich in leafy greens, fish, and other nutrient-dense foods
- Wearing sunglasses to protect your eyes from ultraviolet light
When to See a Retina Specialist
Certain symptoms require immediate attention. See a retina specialist or go to the emergency room right away if you experience any of the following:
- A sudden increase in floaters (spots or strands drifting across your vision)
- Flashes of light in one or both eyes
- A shadow, curtain, or dark area spreading across your field of vision
- Sudden loss of vision in one eye
- Significant eye pain, redness, or light sensitivity after an injection
Some changes happen gradually and can be easy to overlook. Contact your retina specialist if you notice straight lines appearing wavy or bent, a growing blank or dark spot in the center of your vision, increasing difficulty reading or recognizing faces, or any new distortion when checking your Amsler grid. Early detection of disease activity allows your retina specialist to adjust treatment before significant vision is lost.
Even when your vision feels stable, regular visits allow your retina specialist to detect subtle changes using OCT imaging and other diagnostic tools. These changes may not be noticeable to you but can signal that the disease is becoming active again. Keeping all scheduled appointments, even when you feel well, is essential for long-term vision protection.
Questions and Answers
Most injection appointments take about 15 to 30 minutes from start to finish, including preparation and monitoring. The injection itself lasts only a few seconds. The rest of the time involves numbing the eye, cleaning the area, and a brief check afterward. Many patients are surprised at how quick the process is once they have been through it once.
In some cases, anti-VEGF therapy can partially improve vision, particularly when treatment starts early before significant damage to the retina has occurred. About one in three patients see measurable vision improvement. However, the primary goal is to stabilize vision and prevent further loss. Retinal tissue that has been permanently scarred or damaged may not recover. Starting and maintaining treatment early gives you the best chance of preserving the vision you have.
The most common side effects are mild and temporary. They include redness on the white of the eye, a gritty or scratchy feeling, mild soreness, and temporary floaters. Serious complications are rare but can include infection inside the eye (endophthalmitis), retinal detachment, or increased eye pressure. Your retina specialist takes careful precautions to minimize these risks. Report any sudden pain, significant vision change, or worsening redness right away.
Treatment duration varies from person to person. Some patients are able to gradually extend the time between injections and may eventually pause treatment if the disease remains inactive for a prolonged period. Others require ongoing injections to keep the condition controlled. Your retina specialist will monitor your response at each visit and adjust your treatment plan accordingly. The goal is to find the longest safe interval between injections while keeping the disease stable.
All anti-VEGF drugs share the same core function of blocking VEGF to reduce abnormal blood vessel activity. They differ in molecular design, how long they remain active in the eye, and which conditions they are approved to treat. For example, Vabysmo (faricimab) targets an additional protein called angiopoietin-2, while Eylea HD (high-dose aflibercept) uses a higher dose to extend the time between injections. Your retina specialist will recommend the medication that best fits your specific condition, treatment history, and response.