Overview
Drug treatment for diabetic retinopathy is based on intravitreal injections — a medicine delivered directly into the vitreous, close to the retina. It is the first-choice treatment for diabetic macular oedema and for proliferative forms, alongside laser and vitrectomy.
- How it is given
- Outpatient intravitreal injection — topical anaesthetic eye drops.
- Four main classes
- Anti-VEGF, faricimab (bispecific), intravitreal corticosteroids, supportive systemic treatments.
- Aim
- Reduce macular oedema, block neovascularisation and preserve central vision.
- Adherence
- Initial cycles of monthly injections, then personalised — not missing check-ups is essential.
Drug classes
Four treatment groups, chosen and combined according to the stage of retinopathy, the presence of macular oedema and the characteristics of the patient. Anti-VEGF injections are the first choice in most cases.
- 01
Anti-VEGF intravitreal injections
First choiceThey block VEGF (Vascular Endothelial Growth Factor), the molecule that stimulates the growth of abnormal new vessels and increases capillary permeability. They reduce macular oedema and neovascularisation in the proliferative form.
- 02
Faricimab — bispecific anti-VEGF
New generationA new-generation molecule that blocks two targets at once: VEGF (like classic anti-VEGF drugs) and angiopoietin-2. This dual mechanism stabilises the vessels and further reduces inflammation in the retina.
- 03
Intravitreal corticosteroids
Second line or add-onThey reduce inflammation and retinal oedema through several mechanisms. They come as small biodegradable or non-biodegradable implants that release the active ingredient over months.
- 04
Supportive systemic treatments
EssentialEye injections are not enough without control of diabetes and its associated risk factors. Blood sugar, blood pressure, lipid profile and kidney function act on the mechanisms of retinopathy and determine its progression.
Management and monitoring
The effectiveness of intravitreal injection treatment depends on a correct procedure in the operating theatre and on regular check-ups with macular OCT. These are two steps that the patient needs to know about in order to take an active part in their care.
The intravitreal injection procedure
The injection is given as an outpatient procedure in the operating theatre, under topical anaesthesia (eye drops). It takes a few minutes and is generally well tolerated.
Topical anaesthesia with anaesthetic eye drops and thorough disinfection of the eye with iodine.
An eyelid speculum keeps the eyelids open; the medicine is injected through the pars plana (4 mm from the limbus) using a very fine needle.
After the injection: antibiotic drops are instilled and eye pressure is checked. Possible floaters or mild irritation for a few hours.
In the following days, avoid rubbing the eye and follow the clinic's guidance on hygiene, make-up and swimming.
Monitoring with OCT
Treatment success is assessed by visual acuity and macular OCT at every check-up. OCT quantitatively measures retinal thickness and the presence of fluid — it is the main measure used to decide whether to go ahead with the next injection.
OCT at every visit to measure macular thickness and the response to the medicine.
Treat & Extend schedule: if the OCT is dry, the interval is lengthened (usually by 2 weeks); if fluid appears, it is shortened.
Tell your ophthalmologist straight away about a sudden drop in vision, intense pain, severe redness or an increase in floaters.
Side effects
Intravitreal injections are generally safe and well tolerated. Side effects fall into two groups: frequent but mild local effects and serious but rare effects. Active monitoring of the patient is the best prevention of serious complications.
Frequent local effects (mild)
A feeling of pressure or a foreign body, floaters in the hours afterwards, mild redness of the conjunctiva, slight subconjunctival bleeding. All of these symptoms are temporary and resolve on their own within a few days.
Rare but serious effects
Endophthalmitis (intraocular infection) is the most feared complication: rare (1 in 1,000–3,000 injections) but requires urgent treatment. Other rare events include retinal detachment, severe vitreous haemorrhage and raised eye pressure. They present with intense pain, sudden drop in vision and marked redness.
Effects specific to corticosteroids
Implants containing dexamethasone or fluocinolone can cause raised intraocular pressure (in 10-30% of cases) and speed up cataract in phakic patients. For this reason, in phakic patients they are usually second-line treatment.
When to contact your ophthalmologist urgently
Intense eye pain, sudden drop in vision, marked redness, light sensitivity or a marked increase in floaters within 48-72 hours of the injection require an urgent eye examination. These are early signs of endophthalmitis or other serious complications.