6 Eye Symptoms You Should Never Ignore

Blurry vision from macular degeneration or another serious eye condition often first develops in just one eye. But people don’t always recognize it right away, because the other eye tends to compensate.

“You can have really blurry vision in one eye and not even notice it until you cover the other eye,” says Nathan E. Podoll, co-division chief, comprehensive ophthalmology, at the Vanderbilt Eye Institute.

Sudden blurriness can also be a sign of a retinal detachment, a cataract or bad diabetic neuropathy, or it could be caused by a stroke or a brain tumor. It should always prompt immediate medical attention.

3. Straight objects look wavy

If straight objects suddenly appear distorted, that’s usually a symptom of age-related macular degeneration, likely in a more advanced stage, Podoll says.

“Let’s say you have blinds or a door frame in your home that should be straight. If you can see out of one eye or the other that it looks distorted, bent or wavy, that is something you should not ignore,” he explains.

If you have macular degeneration, you may also notice a blurry area or blank spot near the center of your vision, and that colors look less bright than before. You may also have trouble seeing in dim lighting. Your risk is higher if you are white, if you smoke or if you have a family history of the disease.

4. Double vision

If you see two images next to each other or on top of each other, you know something’s not right.

The first thing a doctor will want to know is whether your double vision is in both eyes or just one. You can find out by covering one eye.

If you still see double, then you have monocular diplopia, or double vision affecting one eye. Monocular diplopia is less concerning than double vision affecting both eyes. It can be caused by dry eye syndrome, the beginning stages of a cataract or an age-related change to the shape of your eye.

Double vision that affects both eyes, called binocular diplopia, is more serious, and you should get yourself to an ER, pronto. Binocular diplopia can be a sign of a stroke, a brain tumor or an aneurysm, or it may indicate uncontrolled high blood pressure or diabetes.

5. Extreme redness or swelling

In many cases, redness and swelling are caused by something relatively easy to treat, such as dry eye syndrome or conjunctivitis (pink eye), Podoll says. But an extremely red or swollen eye can also be a sign of a more serious condition, so it’s important to get it checked out.

The most concerning culprit would be an inflammatory condition of the eye, such as uveitis or scleritis. Infection or injury can cause both conditions, but they are most often associated with autoimmune disorders like rheumatoid arthritis or lupus, Podoll says. Other symptoms of scleritis and uveitis include extreme light sensitivity and blurry vision.

Both uveitis and scleritis can cause permanent vision loss if they’re not treated.

6. Eye pain that comes out of nowhere

Sudden eye pain could be caused by internal bleeding, a scratched cornea or dry eye, Di Meglio says. If it’s accompanied by skin tingling, it can be an early symptom of shingles, a viral infection that causes a painful rash.

Probably the most feared cause of sudden eye pain is glaucoma, a serious eye condition caused by increased pressure inside the eye. Most of the time glaucoma has no symptoms, but one type, called acute angle-closure glaucoma, “may feel like a headache or pressure behind your eye,” Di Meglio says. “You may also feel nauseous. If it’s really bad, you may see rainbows around lights. That’s a sign of swelling of the cornea.”

Without treatment, glaucoma can cause vision loss and blindness.

Michelle Crouch is a contributing writer who has covered health and personal finance for some of the nation’s top consumer publications. Her work has appeared in Reader’s Digest, Real Simple, Prevention, The Washington Post and The New York Times.