Anti-VEGF intravitreal injection

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Who benefits from anti-VEGF intravitreal injections?

Diseases that may benefit from anti-VEGF intravitreal therapy are often chronic and include:

Patients with these conditions can experience sudden blurry vision from leakage of the abnormal blood vessels and without anti-VEGF treatment are at risk of blindness or permanent loss of the central vision.

How do anti-VEGF intravitreal injections work?

The anti-VEGF medication is injected into the vitreous gel in the eye. Anti-VEGF medications are antibody fragments designed to target and suppress vascular endothelial growth factor (VEGF), a protein that promotes blood vessels to grow and leak. The medication helps to prevent ongoing damage to the retina light receptors. The fluid and blood under/within the retina should slowly resolve over the course of months and your vision will often improve and stabilize.

How does my ophthalmologist perform my treatment?

A small clip (speculum) is used to keep the eye open and your surgeon will use local anaesthetic drops/gel to numb the surface of the eye. The anti-VEGF medication is injected into your eye with a fine needle. The procedure, in most cases, is performed while you are slightly reclined in the office chair and takes a few minutes, but the injection itself is over in less than 10 seconds.

How many treatments will I need?

Treatments are initially given monthly and then as the disease stabilizes the interval between treatments increases. As the medication effects wear off the disease tendency can return. Many patients require ongoing anti-VEGF injections to keep their eye disease stable and preserve the central vision.

What should I expect after the injection?

You can return to normal activities after the injection and there are no restrictions.  You may have a mild gritty or irritated sensation that can be treated with artificial tears.  

Patients with wet macular degeneration present with leakage of fluid and blood resulting in blurred vision
Monthly treatments with anti-VEGF injections suppresses the disease tendency in macular degeneration and the blood and fluid resolves

Who should not be treated with anti-VEGF drugs?

If you have an allergy to anti-VEGF or any of its ingredients; if you have an infection in or around the eye; if you are pregnant or are already pregnant; if you are breast-feeding.

What are the risk associated with anti-VEGF injections?

Anti-VEGF injections are commonly performed, safe, office-used procedures where complications are rare and for most patients, the benefit of treatment outweighs the small risk of injection complications.  

Common side effects

  • Red eye from a broken blood vessel on the white of the eye (subconjunctival hemorrhage) that usually causes only mild discomfort and has no impact on vision. Subconjunctival hemorrhage will usually resolve without treatment within 2 weeks.
  • Floaters.  Right after the eye injection it is normal to see the medication as blobs or floaters.  This usually settles within a few days.
  • Sore, gritty eye, stingy eye.  The cleaning solutions used to protect the eye from infection can irritate the surface of the eye. This usually resolves within 24-28 hours and can be soothed by artificial tears.
  • Corneal abrasion. Rarely the irritation on the surface of the eye is more severe. In the hours after the injection, the eye has sharp pain and tearing, sometimes with blurry vision.  This will usually heal within 24-48 hours and can be treated with artificial tears.
  • Increase in eye pressure. The injection will cause a temporary rise in eye pressure in many patients.  Your eye surgeon may treat this with drops, or by removing a small amount of fluid from the front of the eye.

Rare but serious potential risks

  • Retinal tear/detachment. Any onset of new flashes (photopsia) or new floaters could be a sign of a retinal tear/detachment and requires a dilated eye exam with your optometrist or your eye surgeon.
  • Cataract. There is a rare risk that the needle touches the natural lens of the eye, creating a clouding called a cataract. The anti-VEGF medication also may increase the risk of cataract formation over time.
  • Endophthalmitis. Infection inside the eye, is an extremely rare (1 in 2500) but serious risk that can occur to any patient in the week after injection.  In endophthalmitis the vision gets very blurry over a few days and the eye becomes achy and red. It requires urgent treatment and carries a risk of permanent vision loss or blindness.
  • Bleeding in the eye.
  • Eye inflammation/vasculitis.
  • Thromboembolic events or stroke. Some scientific studies have shown slight increased risk of stroke in patients receiving anti-VEGF injections.

You should contact your surgeon immediately or proceed to the emergency room if you think you may have one of the serious potential risks described above.

Cataract surgery wait times

Wait times for cataract surgery are updated quarterly, with wait 1 representing how long it takes to get in to see the surgeon in the office, and wait 2, how long it takes after that to get in for surgery.
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