Find Information About:

Drugs & Supplements

Get information and reviews on prescription drugs, over-the-counter medications, vitamins, and supplements. Search by name or medical condition.

Pill Identifier

Pill Identifier

Having trouble identifying your pills?

Enter the shape, color, or imprint of your prescription or OTC drug. Our pill identification tool will display pictures that you can compare to your pill.

Get Started
My Medicine

My Medicine

Save your medicine, check interactions, sign up for FDA alerts, create family profiles and more.

Get Started

WebMD Health Experts and Community

Talk to health experts and other people like you in WebMD's Communities. It's a safe forum where you can create or participate in support groups and discussions about health topics that interest you.

  • Second Opinion

    Second Opinion

    Read expert perspectives on popular health topics.

  • Community


    Connect with people like you, and get expert guidance on living a healthy life.

Got a health question? Get answers provided by leading organizations, doctors, and experts.

Get Answers

Sign up to receive WebMD's award-winning content delivered to your inbox.

Sign Up

Eye Health Center

Font Size

Newer Contact Lenses Don't Cut Infections

Daily Disposables, Newer Materials Have Not Reduced Infection; Overnight Wear Increases Risk Most, Studies Show
WebMD Health News
Reviewed by Louise Chang, MD

Oct. 3, 2008 -- Neither the newer contact lenses that allow more oxygen into the eye nor daily disposable lenses have reduced the risk of a dangerous eye infection as hoped, according to two new studies.

Whatever the type of lens, sleeping with them in is the biggest risk factor for a painful infection of the cornea called microbial keratitis, the researchers also find.

"If you wear any of these lenses overnight, you have five times the risk of infection," says John Dart, DM, a consultant ophthalmologist at Moorfields Eye Hospital in London. He is the lead author of one study and co-author of the other.

"These are the first well-designed studies to look at daily disposables and the newer silicone hydrogel lenses," Dart tells WebMD. The silicone hydrogel lenses were introduced in 1999 in the hope that by improving oxygen transmission to the cornea, which has no blood supply of its own, it would decrease infection risk, he says. Daily disposables, introduced in 1999, were also thought to be protective against infection because they're not exposed to lens cases, which can be contaminated.

But neither of the studies, published in the October issue of Ophthalmology, found that to be true, Dart says.

However, Dart says, it's important to put the risk in perspective. "The risk of getting microbial keratitis is actually overall not large," he says. It affects about 1 in 2,000 contact lens wearers. But it can cause vision loss, sometimes permanently.

Contact Lenses & Infection Risk: The U.K. Study

In the study led by Dart, the researchers evaluated 367 contact lens wearers with microbial keratitis, 1,069 hospital patients who wore contact lenses but had no contact lens-related disorders, and 639 contact lens wearers in the general population.

The hospital patients answered a questionnaire and the control patients in the general population were interviewed by telephone from late 2003 to 2005.

Daily disposable wearers had 1.5 times higher risk of microbial keratitis than those who wore soft lenses that were replaced every one to four weeks, and those who wore rigid gas-permeable lenses had the least risk of infection.

1 | 2 | 3

Today on WebMD

Woman holding tissue to reddened eye
Learn about causes, symptoms, and treatments.
Simple annoyance or the sign of a problem?
red eyes
Symptoms, triggers, and treatments.
blue eye with contact lens
Tips for wearing and caring.
Understanding Stye
human eye
eye exam timing
vision test
is vision correction surgery for you
high tech contacts
eye drop