Cataract surgery is one of the safest and most common surgeries performed today, but it does come with side effects. Nearly everyone experiences some degree of dryness, mild discomfort, and itching in the first few days. More serious complications like infection or retinal detachment are rare, affecting well under 1% of patients. Here’s what to expect and what to watch for.
Common Side Effects in the First Week
Most people feel itching and mild discomfort for a couple of days after surgery. That gritty, sandy feeling in the eye is normal and comes from the small incision made during the procedure. For most people, this heals within about a week. If you already have dry eye, the discomfort can linger for up to three months.
A red or bloodshot spot on the white of the eye is also common, especially with laser-assisted cataract surgery, which uses suction on the eye. It looks alarming but is harmless. The body reabsorbs the blood on its own, though it can take two to three weeks for the spot to fully disappear.
Almost all patients experience some level of dryness afterward. Dry eye can cause light sensitivity and temporarily blurry vision on top of the scratchiness. Your surgeon will typically prescribe eye drops to manage inflammation and prevent infection during this window.
Light Artifacts and Visual Disturbances
The artificial lens implanted during surgery can cause unusual visual effects called dysphotopsia. There are two types. Positive dysphotopsia shows up as bright artifacts: arcs, streaks, starbursts, rings, or halos of light, usually in your central or mid-peripheral vision. Negative dysphotopsia is the opposite, a dark crescent-shaped shadow at the edge of your vision, most often on the side closest to your temple.
Negative dysphotopsia occurs more frequently in women and in the left eye. Both types tend to improve over weeks to months as your brain adapts to the new lens. Lenses with smoother edges produce these effects less often, so if you’re particularly concerned, it’s worth discussing lens options before surgery.
Posterior Capsule Opacification (Secondary Cataract)
This is the most common long-term side effect. During cataract surgery, your natural lens is removed but the thin capsule that held it stays in place to support the new artificial lens. Over time, that capsule can cloud over, gradually blurring your vision again. It’s sometimes called a “secondary cataract,” though it isn’t actually a new cataract forming.
How often does it happen? Studies put the number at roughly 28% of patients within two to three years and around 50% within three to five years. In younger patients, the rate is much higher, approaching 100% within two years. The clouding can develop months or years after the original surgery.
The fix is a quick, painless laser procedure that creates an opening in the clouded capsule. It takes a few minutes in the office, requires no anesthesia beyond numbing drops, and vision typically clears within a day or two.
Swelling in the Retina
Fluid can accumulate in the macula, the central part of the retina responsible for sharp vision. This swelling is one of the more frequent postoperative complications and typically causes blurry or distorted central vision weeks after surgery rather than immediately. Most cases respond to anti-inflammatory eye drops. When drops aren’t enough, stronger treatments like injections can be considered, but the majority of cases resolve without lasting damage.
Rare but Serious Complications
Infection inside the eye (endophthalmitis) is the complication surgeons worry about most. It’s also very rare. A large review of over 200 studies found rates ranging from about 0.06% to 0.19% depending on the type of incision used. The most common modern technique carries the highest rate at roughly 1 in 500, which is still quite low. Symptoms include increasing pain, worsening vision, and pus or discharge from the eye in the days following surgery. This requires urgent treatment.
Retinal detachment is another serious but uncommon risk. Data from a registry of over 3 million eyes found that about 0.21% of patients experienced a retinal detachment within one year of surgery, roughly 1 in 500. Over a longer horizon of 10 years, studies report rates between 0.36% and 2.9%. Warning signs include a sudden increase in floaters, flashes of light, or a shadow creeping across your field of vision.
Capsule complications during surgery itself, where the membrane holding the lens tears, have become less frequent as techniques have improved. The rate dropped from 1.5% in 2007 to 0.8% in 2016. Surgeon experience matters significantly here: high-volume surgeons who perform 1,000 or more procedures a year have a complication rate of just 0.48%, compared to 2.15% for surgeons who do fewer than 100 per year.
Who Faces Higher Risk
People with diabetes face a specific additional concern. A study of over 3,500 patients with type 2 diabetes found that cataract surgery increased the risk of diabetic eye disease progressing in the first year after the procedure. Patients who had diabetes for at least five years were about 1.5 times more likely to see their retinopathy worsen and 2.5 times more likely to develop bleeding inside the eye compared to similar diabetic patients who didn’t have the surgery. This doesn’t mean people with diabetes should avoid cataract surgery, but their eye health needs closer monitoring afterward.
High myopia (severe nearsightedness) also raises the risk of retinal detachment after surgery, since the elongated shape of a highly myopic eye already puts the retina under more stress.
Warning Signs That Need Immediate Attention
Most side effects after cataract surgery are mild and self-limiting. But certain symptoms in the days and weeks afterward signal something that needs prompt evaluation:
- Increasing eye pain (not the mild ache of the first day or two, but worsening pain)
- Pus or discharge draining from the eye
- Vision getting worse instead of gradually improving
- Persistent redness that hasn’t improved after three to four days
- New floaters, flashes of light, or a shadow in your peripheral vision
Any of these warrant a same-day call to your surgeon’s office. Caught early, even serious complications like infection or retinal detachment can often be treated successfully.