Pink Eye: A Complete Guide to Conjunctivitis
A comprehensive look at the contagious eye condition called pink eye or conjunctivitis, including symptoms, causes, treatment, and prevention.
What is Pink Eye?
Pink eye, or conjunctivitis, is a common eye ailment defined as an infection or inflammation of the conjunctiva (the outermost layer of the eyeball), which causes it to becomes red or pink in color. Pink eye can be caused by bacterial infections, viruses, allergies, or contact-lens related problems. There may be discharge, which can irritate the eyes further. Often the condition appears in one eye and then spreads to the other. There are several types of pink eye, and most are contagious. Depending on which type you have, symptoms may last between three and ten days.
How Did I Get Pink Eye?
Pink eye can be contracted numerous ways. You can contract viral or bacterial conjunctivitis simply by touching your eye after touching an infected surface or object such as a doorknob or shopping cart, or by using infected mascara or eye drops. Shaking hands or sharing towels and pillows with someone who is infected can also result in transmission of the disease.
Other times, pink eye develops as a symptom of a systemic, body-wide disease—for example, pink eye is a symptom of chlamydia. If you are subject to seasonal allergies, you may experience pink eye during times of the year when pollen and other allergens fill the air. Over-use of certain types of contact lenses, such as extended-wear lenses, or improperly cleaning contact lenses can also cause this condition. Learn more about common lens-care mistakes.
Is Pink Eye Contagious?
Bacterial and viral pink eye are contagious, but allergic pink eye is not. It can be hard to tell which type you are suffering from, but allergic pink eye usually goes away quickly on its own, or when the irritating agent is removed and the eyes are rinsed out.
The infectious types of pink eye are the ones to be wary of because they can spread very easily, even just by touching or using an article that has been used by an infected person. For example, a person who has pink eye and rubs his eyes and then uses the same hand to open a door could end up infecting someone else who touches that door. This is why people—especially kids—who are diagnosed with pink eye are encouraged to stay home until the infection is cured in order to avoid passing the infection to other people.
Other ways of passing the infection include sharing items like pillowcases, towels, and bathroom washcloths. Most types of pink eye are contagious. If you are exhibiting symptoms of this condition it is very important to contact your doctor so that he or she can properly diagnose which type it is.
Types and Causes of Pink Eye
All forms of pink eye involve inflammation of the conjunctiva. This inflammation turns the white part of the eye pink or red. Let’s go over the various types of pink eye:
- Viral conjunctivitis
- Epidemic keratoconjunctivitis (a form of viral conjunctivitis)
- Bacterial conjunctivitis
- Allergic conjunctivitis
- Eye drop conjunctivitis
- Herpes simplex conjunctivitis
- Giant papillary conjunctivitis
- Vernal conjunctivitis
- Non-infectious conjunctivitis
Viral and bacterial conjunctivitis are the most common types of pink eye. The viral form is caused by the same virus as the common cold, and usually improves on its own over the course of seven to ten days. For the first ten days (or as long as there are symptoms), viral conjunctivitis is very contagious. On rare occasions, it may cause cloudy spots in the cornea.
The symptoms of bacterial conjunctivitis are worse than those of viral conjunctivitis. There are several types of bacteria that cause conjunctivitis, including gonorrhea, staphylococci, and streptococci. Viral and bacterial conjunctivitis are very contagious.
Allergic conjunctivitis is non-contagious and is caused by common allergies such as animal dander, pollen, and dust. Those who use medicated eye drops regularly may develop eye-drop, or “toxi” conjunctivitis, which is caused by the preservatives in certain types of eye drops. Most people can tolerate a moderate to high level of exposure to these preservatives, but others are more sensitive. Avoiding the use of such eye drops generally prevents the condition from recurring.
Herpes simplex conjunctivitis is also caused by a virus, but it differs slightly from normal viral conjunctivitis. Although viral conjunctivitis can cause a burning sensation and pain, with herpes simplex conjunctivitis, the pain and burning may be unbearable. Herpes simplex conjunctivitis also causes additional symptoms such as blisters on the conjunctiva or eyelids. It can be sight-threatening if it spreads to the cornea, but anti-viral drops are available to treat this problem.
Giant papillary conjunctivitis is a non-contagious conjunctivitis usually seen in people who wear soft contact lenses. It is caused by an immunological response to contact lens deposits, or simply by over-wear of the lenses. Certain cleaning solutions may also contribute to this problem. This type of conjunctivitis may require a contact-lens wearer to switch to a different type of contact lens. Soft contact lenses may need to be replaced with rigid gas-permeable (RGP) lenses or daily disposable contact lenses. Changing the cleaning solution may be helpful, but some patients need to stop wearing contact lenses for several weeks, or even forever.
Vernal conjunctivitis is usually found in people and families with a history of allergies, asthma, and eczema. This type of conjunctivitis is defined as long-term swelling of the outer lining of the eyes due to an allergic reaction.
Epidemic keratoconjunctivitis is extremely contagious, and there are often large outbreaks in schools. It is an infectious form of the condition that derives from particular strains of adenovirus—the same virus that causes the common cold—and is spread through contact with infected persons, instruments, and other items. Symptoms of this type of conjunctivitis typically last for less than two weeks, and there is no treatment for it. Like the common cold, it must run its course. This form of conjunctivitis causes blurred vision, which sometimes lasts a few months.
Non-infectious conjunctivitis is typically the result of irritated eyes. Typical irritants are dust, smoke, perfume, and strong chemicals. This type of conjunctivitis can also develop if an irritant is ingested. Allergic conjunctivitis and giant papillary conjunctivitis belong to this category.
Pink Eye Symptoms
Some symptoms are unique to certain types of pink eye. The most noticeable sign is the pink to reddish color of the eyes. Irritation and itchiness are two other common symptoms of conjunctivitis. Tearing is another prevalent symptom, as the eyes naturally produce more tears in order to relieve the discomfort.
Some types of pink eye cause discharge, especially viral and bacterial conjunctivitis. This discharge may be yellow or green, and it can cause the eyelids to stick together or it can flow out of the eyes. Let’s go over the specific symptoms of each form of conjunctivitis:
Viral Conjunctivitis Symptoms
- Watery eyes accompanied by discharge
- The infection usually affects one eye, but it can often affect both
- Eyelid swelling, which may be very severe
- Blurred vision may be a symptom.
Bacterial Conjunctivitis Symptoms
- Watery eyes with yellow or green discharge
- Irritation and redness
- The infection usually starts in one eye and may spread to the other
Allergic Conjunctivitis Symptoms
- Itching and redness
- Swollen or puffy eyes and eyelids
Herpes Simplex Conjunctivitis Symptoms
- Severe burning sensations
- Severe pain
- Blisters may develop on conjunctiva or eyelids
Giant Papillary Conjunctivitis Symptoms
- Inability to tolerate contact lenses
- Large amount of discharge
- Excessive tearing
- Red bumps on underside of eyelids
- Itching, especially after removal of the lenses.
Vernal Conjunctivitis Symptoms
- Burning and watery eyes
- Photophobia (discomfort in bright light)
- Bumps may appear on underside of eyelids
- Area around cornea may become swollen and rough
Epidemic Keratoconjunctivitis Symptoms
- History of recent cold symptoms or sore throat
- Redness and irritation of the eyes
- Light sensitivity (photophobia)
- Thin, watery discharge
- Swollen lymph nodes on affected side
- Blurred vision
- Severe swelling of the eyelids
Diagnosing Pink Eye
Diagnosing pink eye usually begins with a complete history and physical examination. Infectious forms of conjunctivitis are diagnosed by their symptoms and appearance. In general, a slit lamp examination is performed. The slit lamp magnifies the surface of the eye and allows the eye doctor to see an inflamed conjunctiva, infected cornea, or infected anterior chamber (the front part of the eye).
Viral conjunctivitis is harder to diagnose, and can be distinguished from bacterial conjunctivitis solely by its appearance, but this form of pink eye is usually accompanied by a cold symptoms or a sore throat. Samples may be taken and sent to a laboratory to identify the infectious organism. In most cases, samples are taken when gonorrhea or chlamydia is suspected, pink eye is severe, or the condition is recurrent.
How to Avoid Pink Eye
Avoiding pink eye is not difficult. Here are some basic ways to prevent pink eye from spreading:
- Wash your hands frequently
- Use antibacterial hand sanitizer frequently, especially if you are unable to wash your hands with soap and water
- If allergic conjunctivitis is the problem, remove yourself from the area in which the allergens are present
- Use cold compresses on your eyes periodically to lessen symptoms if due to allergies; use warm compresses several times per day for all other types
- Avoid touching your eyes directly
- Avoid sharing towels, washcloths, make-up, goggles, sunglasses, eye drops, or pillows
- Keep your eyewear clean at all times
- Disinfect common household items frequently, especially if a member of the household has pink eye
- If you have pink eye, discontinue using current contact lenses, make-up, and eye drops, and do not replace or resume using product until condition is gone
Pink Eye Treatment
Treatment depends on what type of the disease you have. Pink eye typically resolves without serious complications within a week or two, with or without treatment, although symptoms may last up to six weeks. Other times, such as with allergic conjunctivitis, the condition may disappear after removing the allergen.
For bacterial infections, a doctor must prescribe an antibiotic to attack the bacteria. This medication can be delivered in eye drops or ointments that are applied to the eyes. Pink eye caused by allergies can be treated with over-the-counter anti-histamine allergy eye drops.
Over-the-counter medications are all that is required for most cases of viral pink eye—the virus just needs to run its course, and medication is used just to soothe the symptoms. Antibiotics do not work against viruses. Warm compresses are great for removing the sticky residue around the eyes. If herpes simplex conjunctivitis is present, a doctor may prescribe anti-viral medicines. Some types of conjunctivitis require mild steroids to be applied directly to the surface of the eye. In general, steroids are only used in severe cases.
Complications of Pink Eye
There are several complications that can arise from pink eye:
- Blurred and/or reduced vision
- Scarring of the cornea or additional problems with cornea
- Spreading the condition to others
- Abscess around the eye
- Long-term dry eye symptoms
Talking to Your Eye Doctor
Here are some questions to ask your eye doctor about pink eye:
- How did I get pink eye?
- What can I do to prevent my pink eye from spreading to others?
- How long will I need to stay away from work, school, public places, etc?
- Which type of pink eye do I have?
- If treatment is not working, how long should I wait to contact you again?
- J. Weizer, MD and J.D. Stein, MD, MS “Reader’s Digest Guide to Eye Care” (Quantum Publishing Ltd, 2009) 52-54
- M. Beers, MD “The Merck Manual of Medical Information” 2nd Home Edition (Pocket Books, 2003) 1296-1297
- J. Anshel, MD “Smart Medicine for Your Eyes – A Guide to Natural, Effective, and Safe Relief of Common Eye Disorders” (SquareOne Publishers, 2011) 294-295