Ignore the itch that begs to be scratched.

While rubbing our eyes may seem like a harmless way to relieve itching or dryness, we may want to think twice about the habit, an ophthalmologist warns.

The second-nature response could actually bring a range of risks to the sensitive area, from spreading bacteria to more serious injuries that require surgery.

Reaching up to relieve your eyes of itchiness is often because of allergic conjunctivitis, an inflammatory reaction of the clear skin of the surface of the eye that accounts for nearly half of eye-itching cases.

Other times, it can be due to dermatitis or inflammation of the eyelid skin.

But according to an article written for The Conversation by Taylor Starnes, a board-certified ophthalmologist, trying to relieve whatever’s causing itchy eyes can lead to red eyes, scratches, infection or even disease.

The most serious risk of eye rubbing is keratoconus, a condition where the clear window in front of the eye (or cornea) becomes thinner and irregular in shape.

A healthy cornea has a spherical, dome shape, while one affected by keratoconus becomes more cone-shaped over time.

The condition can also bring on astigmatism, which causes a curved cornea that leads to blurry vision.

Keratoconus can be treated with a procedure called corneal cross-linking that strengthens the cornea and halts the progression of the disease.

However, many patients need special and expensive contact lenses after the treatment for better vision. Some more advanced patients may even need corneal transplants.

Aggressively rubbing your eyes can also cause a scratch in the skin of the eye, known as a corneal abrasion, which, if your fingernail catches it, requires antibiotic treatment to prevent infection.

Or you can inadvertently cause a subconjunctival hemorrhage by breaking a blood vessel on the surface of the eye and making it appear red.

While it may look alarming, a subconjunctival hemorrhage is simply a bruise on the surface of the eye and only lasts a couple of weeks with no permanent damage.

And when you touch your eyes, you’re transferring a whole lot of germs, including staphylococcus aureus and streptococcus, from everything you touched, like door handles, phones and laptops.

This can bring about viral conjunctivitis, commonly known as pink eye, that brings a red, oozing and crusty mess to the eyes.

Oftentimes, there’s no prescription treatment for pink eye, but washing your hands before touching your eye is highly recommended by Starnes.

While rubbing our eyes is second nature for many, there are over-the-counter treatments that can address the underlying conditions causing dryness.

For example, eye drops can help flush out the microscopic debris that causes itchy, watery eyes associated with allergies.