What anti-VEGF injection does
Diabetic macular edema is swelling of the macula, the central part of the retina, caused by leaky vessels. Vascular endothelial growth factor (VEGF) promotes both leakage and new vessel growth. An intravitreal anti-VEGF injection delivers a drug directly into the vitreous through the white of the eye to block VEGF, reduce swelling, and improve or preserve central vision. Injections are often given repeatedly over months.
The expected finding
A small red patch on the white of the eye at the injection site, a subconjunctival hemorrhage, is common and harmless after an intravitreal injection. It comes from a tiny surface vessel broken by the needle and fades over one to two weeks. A mild scratchy or gritty feeling for a day, often from the antiseptic used to prepare the eye, is also expected. The nurse reassures the client that this patch does not affect vision and needs no treatment.
Warning signs of endophthalmitis
The most serious complication is endophthalmitis, an infection inside the eye that can destroy vision within hours to days. Its signs are increasing eye pain, worsening vision, spreading redness of the whole eye, discharge, and light sensitivity, typically appearing in the first days after injection. Raised eye pressure and retinal detachment are other complications. Any of these must be reported the same day.
| Finding after injection | Expected? | Action |
|---|
| Small red patch at the site | Yes | Reassure |
| Mild scratchy feeling | Yes | Reassure; lubricating drops if ordered |
| Dimmer central vision | No | Report the same day |
| Whole-eye redness with yellowish discharge | No | Report the same day |
| Pain worse than on injection day | No | Report the same day |
Why the other findings must be reported
Central vision dimmer than before the injection, redness of the whole eye with yellowish discharge, and pain that is worse than on the day of injection are each a warning sign of infection or raised pressure. They are the opposite of the expected course, in which comfort improves day by day. Even with a mild-looking symptom, the safer path is same-day review because early treatment of endophthalmitis protects vision.
Exam takeaway
Key point After an intravitreal injection, a small red spot at the site is expected. Increasing pain, worsening vision, spreading redness, or discharge suggests endophthalmitis and is reported at once.