Eye injections
What intravitreal injections are, the conditions they treat, and what to expect.
What is an intravitreal injection?
Intravitreal injections are given into the vitreous cavity — the back part of the eye filled with vitreous gel. They are used to deliver medication directly to the retina for conditions including wet macular degeneration, diabetic macular oedema, and retinal vein occlusion.
Injections are usually given as a course, typically one month apart for a minimum of four months, potentially continuing for many months depending on response. Some conditions require a single injection or less frequent dosing. There are different drugs available — including ranibizumab (Lucentis), aflibercept (Eylea), and faricimab (Vabysmo) — and they work by reducing leakage of fluid from abnormal blood vessels at the macula.
What to expect
The injection is given as an outpatient procedure and takes only a few minutes. You will have dilating and anaesthetic drops. You lie on a couch, the eye area is cleansed, and a small device keeps the eyelids open. The injection itself is very quick.
Afterwards, your vision will be checked. Most people have no adverse effects. The commonest is some redness at the injection site. Some people notice a slight ache for a few hours.
When to seek urgent advice
The most serious risk is a severe eye infection (endophthalmitis). Contact your doctor immediately if you develop increasing pain, increasing redness, or decreasing vision after an injection.