Eye injections deliver medication directly into the gel-filled interior of the eye to treat conditions that threaten vision, most commonly wet age-related macular degeneration (AMD), diabetic retinopathy, and retinal vein occlusion. The injections target problems happening at the retina, the light-sensitive tissue at the back of the eye, where leaking or abnormal blood vessels can cause swelling and permanent vision loss if left untreated. About 90% of treated eyes maintain or improve their vision over three years of treatment.
Conditions Treated With Eye Injections
The most common reason for eye injections is wet AMD, a form of age-related macular degeneration where abnormal blood vessels grow beneath the retina and leak fluid. This fluid distorts central vision, making faces, text, and fine details look blurry or wavy. Without treatment, these vessels can scar the macula (the part of the retina responsible for sharp, straight-ahead vision) and cause irreversible loss.
Diabetic retinopathy is the second major indication. High blood sugar damages the tiny blood vessels in the retina over time, and in more advanced stages those vessels leak fluid into the macula, a condition called diabetic macular edema. Eye injections reduce that swelling and help preserve vision. Retinal vein occlusion, where a blood clot blocks one of the veins draining blood from the retina, causes similar leakage and swelling and is treated the same way.
Less commonly, eye injections deliver steroids to calm inflammation inside the eye from conditions like uveitis. Antibiotics, antifungals, and antiviral drugs can also be injected to treat serious eye infections such as endophthalmitis (an infection inside the eyeball) or viral retinitis.
How the Medication Works
The most widely used eye injections contain drugs that block a protein called VEGF (vascular endothelial growth factor). Your body normally uses VEGF to grow new blood vessels, but in these retinal diseases the protein is overproduced. Excess VEGF triggers the growth of fragile, leaky blood vessels beneath the retina and makes existing vessels more permeable, allowing fluid and blood to seep into surrounding tissue. That fluid buildup is what blurs and distorts vision.
Anti-VEGF drugs bind to this protein and neutralize it, which does two things: it slows or stops abnormal vessel growth, and it reduces the leakiness of vessels that are already there. As fluid reabsorbs, retinal swelling goes down and vision often improves. The effect is temporary, which is why repeated injections are necessary to keep the disease in check.
Steroid injections work differently. Rather than targeting blood vessel growth, they suppress the broader inflammatory response that drives swelling in conditions like uveitis or certain cases of macular edema that don’t respond well to anti-VEGF treatment alone.
What Happens During the Procedure
Eye injections are done in a doctor’s office or clinic, not an operating room. The entire process takes only a few minutes. Your eye doctor will start by putting numbing drops (a local anesthetic) into your eye. These take a couple of minutes to fully work. While they’re taking effect, the doctor prepares the syringe.
Next, the surface of your eye and the surrounding skin are cleaned with an antiseptic solution to minimize infection risk. A sterile drape is placed over your face with only the treated eye exposed. A small device called a speculum holds your eyelids open so you don’t need to worry about blinking. Some doctors also place an anesthetic-soaked pad on the injection site for an extra minute of numbing.
The doctor then measures a precise spot on the white of the eye, a safe distance from the cornea, and inserts a very fine needle through the outer wall of the eye into the gel-filled cavity behind the lens. The medication is injected, the needle is removed, and you’re done. Most people feel pressure rather than sharp pain, and the actual injection takes only a second or two.
Recovery and Side Effects
You can usually go home right after the injection. It’s normal to have mild tearing, a scratchy feeling, or slight burning for about a day. Many people notice small floating spots or swirls drifting across their vision afterward. With anti-VEGF drugs, these typically clear within a few hours to a couple of days. Steroid injections can leave floaters that take weeks or even months to disappear.
A red spot on the white of your eye at the injection site is very common. This is a small bruise called a subconjunctival hemorrhage, similar to a bruise on your skin. It may change color as it heals and usually fades within two weeks. Vision may be temporarily reduced right after the injection but improves as the eye settles.
The most serious risk is endophthalmitis, a bacterial infection inside the eye. This is rare. A large meta-analysis found it occurs roughly once in every 3,200 to 5,900 injections depending on how the medication is prepared, with prefilled syringes carrying a lower risk than medications drawn from glass vials. Symptoms of endophthalmitis include increasing pain, worsening redness, and significant vision loss in the days following an injection. It requires urgent treatment but is uncommon enough that millions of injections are given safely each year.
How Often Injections Are Needed
Treatment typically begins with three monthly injections, sometimes called the “loading phase.” This initial series establishes a therapeutic level of the drug inside the eye and gives the doctor a baseline for how your eye responds. After that, the schedule varies.
Some patients continue with fixed monthly injections. Others follow a “treat and extend” approach, where the interval between injections is gradually lengthened as long as the eye remains stable. If signs of leakage return, the interval is shortened again. A third approach is “as needed” treatment, where you receive injections only when monitoring shows the disease is active. Your doctor chooses the strategy based on how your eye responds and how consistently you can attend appointments.
For wet AMD, treatment is often ongoing for years, sometimes indefinitely. Diabetic macular edema and retinal vein occlusion may also require long courses of treatment, though some patients eventually stabilize enough to stop or significantly reduce their injection frequency.
How Well They Work
Anti-VEGF injections have transformed outcomes for conditions that once led to severe vision loss. In a real-world study of wet AMD patients, 90% of treated eyes had stable or improved vision after an average follow-up of three years. Before these drugs were available, most people with wet AMD experienced progressive, irreversible decline.
Results depend on starting treatment early, before significant scarring has formed at the retina, and on keeping up with the injection schedule. Skipping or delaying appointments can allow fluid to re-accumulate and damage to progress. The injections control the disease rather than cure it, so consistent follow-up is a key part of maintaining the vision gains they provide.