Diabetic Retinopathy
DR Verified · Sep 2026NEI: "Diabetic retinopathy is an eye condition that can cause vision loss and blindness in people who have diabetes. It affects blood vessels in the retina (the light-sensitive layer of tissue in the back of your eye)." StatPearls: "Diabetic retinopathy (DR) is a microvascular disorder occurring due to the long-term effects of diabetes mellitus."
The nurse’s part in diabetic retinopathy is mostly prevention and detection: make sure every patient with diabetes gets a dilated eye exam, coach the diabetes ABCs, and teach which vision changes mean call now. After an anti-VEGF injection, a red, painful, light-sensitive eye or a change in vision needs immediate care from an ophthalmologist.
What’s going wrong in the body
The normal physiology, where it fails, and why the body’s compensation backfires.
01 How high blood sugar damages the retina
"Diabetic retinopathy is caused by high blood sugar due to diabetes." "The damage to your eyes starts when the sugar in your blood causes changes to the tiny blood vessels that go to your retina. These changes make it harder for the blood to flow, leading to blocked blood vessels that leak fluid or bleed. To make up for these blocked blood vessels, your eyes then grow new blood vessels that don’t work well. These new blood vessels can leak or bleed easily" (NEI).
The biochemistry. "Chronic hyperglycemia is considered to be the primary pathogenic agent in DR." In the polyol pathway, "glucose is reduced to sorbitol by the aldose reductase enzyme. The impermeability of sorbitol leads to its accumulation in all retinal cells leading to osmotic damage to the cells." The combined result is "increased vascular permeability and microvascular occlusion. Retinal ischemia, which occurs as a consequence of microvascular occlusion, leads to the formation of IRMA (intraretinal microvascular abnormalities) and neovascularization" (StatPearls).
The vessel changes. "The morphological changes seen in small retinal vessels in DR include early loss of pericytes, basement membrane thickening, loss of endothelial cells, increased vascular permeability, platelet aggregation, leukostasis, and capillary dropout" (StatPearls).
VEGF — the target of treatment. "VEGF also results in macular edema and results in vasculogenesis, which results in further retinal disease" (StatPearls). Anti-VEGF medicines "block the growth of abnormal blood vessels in the eye" and "can also stop fluid leaks" (NIDDK).
It can start early. NIDDK: damage "can begin during prediabetes." "Damaged blood vessels may leak fluid and cause swelling. New, weak blood vessels may also begin to grow."
02 Stages: nonproliferative, proliferative, and macular edema
[NPDR] Early stage. "In early diabetic retinopathy, blood vessels can weaken, bulge, or leak into the retina. This stage is called nonproliferative diabetic retinopathy" (NIDDK). CDC: "Blood vessels in the retina weaken and bulge, forming tiny pouches. These pouches can leak, which may cause a part of the retina called the macula to swell and distort your vision." "Microaneuryms are the earliest clinically detectable lesions" (StatPearls); cotton wool spots "represent focal infarcts of the precapillary arterioles."
[PDR] Advanced stage. "If the disease gets worse, some blood vessels close off, which causes new blood vessels to grow, or proliferate, on the surface of the retina. This stage is called proliferative diabetic retinopathy. These abnormal new blood vessels can lead to serious vision problems" (NIDDK). CDC: "With minor bleeding, you may see a few dark spots that float in your vision. If there's a lot of bleeding, your vision may be completely blocked."
How fast it moves (StatPearls). "Sixteen percent of cases of mild NPDR and 23% of cases of moderate NPDR progress to proliferative stages within four years"; "Fifty percent of severe NPDR and 75% of cases of very severe NPDR progress to PDR within one year." And the hopeful half: "The initial stages of diabetic retinopathy are reversible if proper glycemic control is achieved."
[DME] Macular edema. "DME happens when blood vessels in the retina leak fluid into the macula (a part of the retina needed for sharp, central vision). This causes blurry vision" (NEI). The macula is the part "that you need for reading, driving, and seeing faces" (NIDDK). CDC calls macular edema "the most common cause of blindness in people with DR." StatPearls: "The first-line treatment usually involves anti-vascular endothelial growth factor (VEGF) therapy."
Iris vessels. "Neovascularization of Iris (NVI) is a marker of poor prognosis and is associated with the propensity to develop neovascular glaucoma" (StatPearls). CDC: neovascular glaucoma "happens sometimes with diabetic retinopathy when new and abnormal blood vessels grow on the iris."
03 Why treatment works best early
"The sooner you’re treated for DR, the better that treatment will work. That's why early diagnosis is so important, even if you don't have symptoms yet" (CDC). NIDDK: "Finding and treating diabetic retinopathy early can reduce the risk of blindness by 95 percent."
What treatment can and cannot do. NEI: "While it won’t undo any damage to your vision, treatment can stop your vision from getting worse." "Anti-VEGF treatments can stop further vision loss and may improve vision in some people," whereas "laser treatment is less likely to bring back vision you’ve already lost compared with anti-VEGF medicines" (NIDDK).
[EWDR] A caution when control is intensified. A systematic review found early worsening of retinopathy "in a wide range of prevalences; 3.3–47% of participants within 3–84 months after intensification of glycaemic control," and "The occurrence of EWDR and progression of retinopathy were found to have an association with the amplitude of HbA1c reduction" (Akil et al., 2022). It is an association to watch for with eye checks, not a reason to keep glucose high — NEI: "Managing your diabetes is the best way to lower your risk of diabetic retinopathy."
Causes & risk factors
Modifiable factors are teaching targets — the patient can act on them.
Signs & symptoms
Each finding tied to the mechanism that produces it — and the triage it calls for.
Diagnostics
Complications
Medications for this condition
Why each class is prescribed here — every card links to its full pharmacology page.
Glycemic control prevents and slows DR. NEI: keep blood sugar in range by "carefully following your doctor’s instructions for your insulin or other diabetes medicines." "The initial stages of diabetic retinopathy are reversible if proper glycemic control is achieved" (StatPearls). When glycemic control is intensified quickly, early worsening of retinopathy has an association with "the amplitude of HbA1c reduction" (systematic review) — a reason for eye checks, not for loosening control.
Same role. "Managing your diabetes is the best way to lower your risk of diabetic retinopathy. That means keeping your blood sugar levels in a healthy range" (NEI). StatPearls: "HbA1c level should be kept below 7%."
Beyond medications
- [AVEGF] Anti-VEGF injections (no class page). "Your doctor may treat your eyes with anti-VEGF medicine, such as aflibercept, bevacizumab, or ranibizumab" (NIDDK); "The doctor will inject an anti-VEGF medicine into your eyes during office visits" and "Your doctor will use medicine to numb your eyes so you don’t feel pain." Aflibercept (EYLEA) and ranibizumab (LUCENTIS) are labeled for "Diabetic Macular Edema (DME)" and "Diabetic Retinopathy (DR)"; bevacizumab "is not FDA approved. Hence it is available only for off-label use" (StatPearls).
- [PDR] Laser. "Laser treatment, also called photocoagulation, creates tiny burns inside the eye with a beam of light" (NIDDK). "Panretinal photocoagulation (PRP) has been considered the standard treatment of proliferative diabetic retinopathy for ages" (StatPearls).
- Vitrectomy. "Vitrectomy is a surgery to remove the clear gel that fills the center of the eye, called the vitreous gel" (NIDDK). If silicone oil is used, "the patient should be explained the need for a mandatory second surgery to remove oil" (StatPearls).
- Steroids. "Other medicines, called corticosteroids, can also help" (NEI); long-acting implants "are reserved for cases not responding to multiple injections of Anti-VEGF medications" (StatPearls).
- The diabetes ABCs. Manage "blood glucose , blood pressure , and cholesterol , sometimes called the diabetes ABCs" and "If you smoke, get help to quit smoking" (NIDDK). CDC: "Physical activity protects your eyes and helps you manage diabetes." NIDDK: "It’s never too late to begin."
- Low vision rehabilitation. "Ask your eye care professional to help you find a low vision and rehabilitation clinic" (NIDDK).
Nursing considerations
The RN-specific layer — each action paired with the reason it matters.
How a real nurse thinks
The clinical-judgment loop, worked for a typical presentation — reasoning, not reference.
- 1 Recognize cues
The day after an intravitreal injection: red, painful, light-sensitive eye with worse vision. Background: poor glucose and blood-pressure control and an overdue exam for the other eye.
- 2 Analyze cues
In the days after an injection, patients "are at risk of developing endophthalmitis, retinal detachment, or retinal vasculitis with or without occlusion" (EYLEA label). A red, painful, light-sensitive eye with a vision change is exactly the combination the label says needs immediate care.
- 3 Prioritize
Save the eye first: same-day ophthalmology assessment. Glucose and blood-pressure control and her overdue exam matter, but they come after.
- 4 Generate solutions
Arrange immediate care from an ophthalmologist today; tell her not to drive with the reduced vision; then plan diabetes ABC coaching and a dilated exam for the left eye.
- 5 Take action
Tell her to come in now (arranging transport), notify the ophthalmologist, and document the symptoms and timing after the injection. Reinforce later that she should not drive "until visual function has recovered sufficiently."
- 6 Evaluate
She is seen the same day. Once the eye is treated, she can explain why a red, painful eye after an injection needs immediate care, she has a dilated-exam appointment for the left eye, and she has a plan with her primary team for glucose and blood pressure.
Scenario — you’re the nurse
Work each question before revealing the answer. Rationales explain the wrong options too.
A 58-year-old woman with type 2 diabetes for 15 years, hypertension and center-involving diabetic macular edema had an aflibercept injection in the right eye yesterday. She calls the clinic nurse.
Q1 Select all that apply Which findings after an anti-VEGF eye injection require immediate care from an ophthalmologist? Select all that apply. - A. Eye becomes red and painful
- B. New sensitivity to light
- C. A change in vision
- D. Blurred vision for a few hours after pupil-dilating drops at the exam
- E. Mild temporary visual disturbance right after the injection that is clearing
Reveal answer & rationale
Q2 Multiple choice A patient with proliferative diabetic retinopathy calls saying she suddenly sees flashes of light, many more floaters than usual and a dark curtain over part of her vision. What is the best response? - A. Book the next routine clinic appointment
- B. Seek emergency eye care now
- C. Rest the eyes and call back if it persists for a week
- D. Check her blood glucose and recheck vision in 2 hours
Reveal answer & rationale
Q3 Multiple choice A patient newly diagnosed with type 2 diabetes asks when he needs an eye exam. What does the nurse teach? - A. Only if vision changes
- B. Now, at diagnosis, and then at least once a year
- C. Five years after diagnosis
- D. Every 5 years if vision is normal
Reveal answer & rationale
Q4 Multiple choice A patient with diabetic retinopathy asks whether laser treatment will bring back the vision she has lost. Which response is accurate? - A. Yes, laser restores most lost vision
- B. Laser mainly keeps the disease from getting worse and is less likely to restore vision already lost
- C. Laser is only used for cataracts
- D. Laser is no longer used for diabetic retinopathy
Reveal answer & rationale
Common questions
What causes diabetic retinopathy?
What are the early signs of diabetic retinopathy?
Can you have diabetic retinopathy and see perfectly well?
Why did my vision blur when my diabetes medicine changed?
Does pregnancy affect diabetic retinopathy?
Do I need to stop aspirin because of retinopathy?
Sources
- Diabetic Retinopathy — StatPearls — StatPearls (NCBI Bookshelf)
- Diabetic Macular Edema — StatPearls — StatPearls (NCBI Bookshelf)
- Vitreous Hemorrhage — StatPearls — StatPearls (NCBI Bookshelf)
- Diabetic Retinopathy (last updated Sept. 11, 2025) — National Eye Institute (NIH)
- Vision Loss and Diabetes (May 2024) — Centers for Disease Control and Prevention
- Diabetic Eye Disease (last reviewed May 2017) — National Institute of Diabetes and Digestive and Kidney Diseases (NIH)
- EYLEA (aflibercept) injection — prescribing information — FDA / DailyMed
- LUCENTIS (ranibizumab) injection — prescribing information — FDA / DailyMed
- Early Worsening of Retinopathy in Type 1 and Type 2 Diabetes After Rapid Improvement in Glycaemic Control: A Systematic Review — Diabetes Therapy (2022) — Diabetes Therapy (PMC, CC BY-NC 4.0)
Reviewed by Hae Suk Lee, RN
Educational summary for nursing students. Scenarios are fictional teaching cases. Always verify against current guidelines and your institution's protocols before acting in practice. Not medical advice.