What Is Pink Eye, or Conjunctivitis?

Here's what you need to know about the condition.

Pink eye, also known as conjunctivitis, can affect everyone from children to adults. Pink eye gets its name from causing a bloodshot hue in the eye, and it can affect one or both eyes. It's a condition experienced on a global basis and tends to be a common reason for medical and ophthalmological office visits, per a Journal of Ophthalmic & Vision Research review published in July 2020. Below is more about pink eye, including information such as symptoms, causes, treatment, and more.

What Are the Signs and Symptoms of Pink Eye?

The inflamed conjunctiva (the clear film covering the inner eyelid and the white part of the eye) makes blood vessels appear larger than normal. The eye appears pink or red, and the inner eyelid can get puffy and pink, too. According to MedlinePlus, symptoms of pink eye can include redness, itching, excess tearing, eye pain, blurred vision, and sensitivity to light.

Eye discharge may vary depending on the type of pink eye.People with pink eye may also find that their eyelashes get stuck together, MedlinePlus says. After a night of sleep, their eyelids may crust over and may even be dried shut.

What Causes Pink Eye—And How Contagious Is It?

The most common causes of conjunctivitis are infections, such as viruses and bacteria; allergens; and other irritants. Also, although all cases of pink eye are not contagious, you should treat any cases of pink eye as being contagious until you determine the type of infection you have.

Viral and Bacterial Conjunctivitis

Viruses are the leading cause of infectious pink eye, per the 2020 Journal of Ophthalmic & Vision Research review, and may be diagnosed based on medical history and symptoms.Pink eye that appears with a cold or upper respiratory infection increases the likelihood that a person's pink eye symptoms are due to a virus.

Bacterial pink eye is more common in children due to close contact with others in school and daycare. Newborns are also at risk of getting pink eye from mothers with sexually transmitted infections (STIs) such as chlamydia and gonorrhea.

Direct or indirect contact with an infected person's eye secretions can cause pink eye to spread. People can pick up pink eye by touching the hands of someone who has it or by touching infected surfaces and then touching their eyes.Viral conjunctivitis can be spread by sneezing or coughing in close proximity to another person. Bacterial pink eye can be transmitted through used washcloths, towels, and pillowcases.

Allergen or Irritant Conjunctivitis

Allergic pink eye occurs when the body mounts a response to an allergen, such as pollen, mold, animal dander, or dust, MedlinePlus says.Some cases of pink eye are due to other environmental irritants. Specifically, chemicals, such as chlorine from swimming pools; air pollution due to vapors, fumes, or smoke; and other irritants, such as cosmetics or contact lenses, can trigger symptoms of pink eye.

Allergic pink eye can also be seasonal. It may occur along with other allergy symptoms, like sneezing and an itchy nose, and often affects people in families with a history of hay fever (also known as allergic rhinitis), asthma, or eczema, according to the Centers for Disease Control and Prevention (CDC).

There's no risk of transmission if the cause of conjunctivitis is an allergen or irritant. Allergic pink eye occurs when the body unleashes a response to pollen, dust mites, animal dander, or another allergen. Irritants, such as cosmetics or chlorine in pool water can cause pink eye, but in this case, the condition cannot be passed along to someone else.

How Does Pink Eye Affect Children?

Bacteria and viruses that cause pink eye are easily transmitted from hand to eye, which is why toddlers and school-aged children are especially at risk. Pink eye outbreaks are common in schools and daycares, Johns Hopkins Medicine notes.

With neonatal conjunctivitis (sometimes also known as ophthalmia neonatorum according to MedlinePlus), newborn babies' eyes may be infected during vaginal delivery if, as noted, the mother has an untreated STI (such as chlamydia or gonorrhea) as well as from other non-sexually transmitted bacteria and viruses.

What the Condition Looks Like: Pictures of Pink Eye

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Dimarik/Getty Images

The conjunctiva swells up, making blood vessels appear larger than normal. Eyelids become pink and puffy.

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Vchal/Getty Images

When allergens—or other irritants—are the culprit, pink eye is very itchy and produces a watery discharge.

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Offstocker/Getty Images

In newborns, pink eye causes red, puffy eyelids. Children may also have thick, green or clear, thin drainage; stringy discharge; or pink or red discoloration of the whites of their eyes, according to Johns Hopkins Medicine.

pink-eye-child-closeup
Sharon Mccutcheon/Getty Images

How Is Pink Eye Diagnosed?

Healthcare providers diagnose pink eye based on a patient's medical history, eye exam, and other physical signs and symptoms. Redness and swelling are common, but other symptoms of pink eye may depend on the underlying cause. Often, the consistency and color of eye discharge provide important diagnostic clues as well per the CDC.

Diagnostic tests are usually not necessary for viral or allergic pink eye. However, if bacterial conjunctivitis is suspected, a healthcare provider may collect a sample of eye secretions for laboratory testing to determine the type of bacteria and the best treatment. Testing may also be ordered if the patient has severe inflammation or recurrent eye infections or does not respond to treatment.

What Options Are Available for Treating Pink Eye?

Pink eye remedies vary depending on the cause and the individual affected. According to the CDC, many cases get better in a matter of days without medication. Instead, home remedies may be helpful. For example, you can try to apply a warm, moist compress to the eye several times a day to relieve swelling and irritation due to viral or bacterial infection.

Specific Treatments by Type of Pink Eye

Viral pink eye usually clears up on its own in a week or two without treatment. It can take longer—around two to three weeks, the CDC says— if complications occur. Antiviral medicines may be prescribed for more serious cases(such as pink eye caused by the herpes simplex virus).

Mild cases of bacterial conjunctivitis often improve in a matter of days without treatment but can last up to two weeks. Antibiotic eyedrops or ointments can speed recovery, reduce complications, and lower the risk of transmission, according to the CDC. Antibiotic treatment is generally recommended for serious symptoms, for people with weak immune systems, and for people whose symptoms do not improve.

Allergic pink eye usually clears up after exposure to the allergen is reduced or eliminated or when treatment is given. Allergy medicines and certain eye drops may provide symptom relief. Pink eye caused by irritants typically improves after the irritant is removed. People who get pink eye from wearing contact lenses may need to switch to a new pair of lenses, a new disinfection solution, or even take a break from wearing contacts.

Pink Eye Treatment for Children

Depending on the type of conjunctivitis a newborn develops, they may need oral or intravenous antibiotics, eye drops, or ointments to ward off potentially serious complications. Compresses may be used to ease swelling and irritation, and allergy medicines may help kids with allergic pink eye. Antibiotic drops are only prescribed for bacterial forms of pink eye.

Sometimes babies develop pink eye after receiving routine eye drops given after birth to prevent eye infection. The irritation usually clears up within a few days. Newborns can also develop red, irritated eyes due to a clogged tear duct. Parents can usually treat it at home by using a clean hand to gently massage the area between the baby's eye and nose.

Ultimately, see a healthcare provider to help determine the cause of your child's symptoms and appropriate treatment.

How To Prevent Pink Eye

Good hygiene can go a long way toward preventing the transmission of pink eye. To protect yourself from reinfection, and others from acquiring pink eye, follow these tips from the CDC:

  • Wash your hands frequently with soap and water.
  • Try not to touch or rub your eyes, especially if you have pink eye in one eye—you might infect the other eye.
  • Use a clean cloth or fresh cotton ball to clear mucus and pus from your eye. Throw away used cotton balls immediately after use, and launder washcloths in hot water and detergent.
  • Wash your hands after applying eye drops or ointment for pink eye and after close contact with someone who has pink eye.
  • Do not share personal items that may have touched your eyes (e.g., towels, bedding, and cosmetics) sheets, pillowcases, and cosmetics.
  • Wash the bath and bed items, used by a person with pink eye, in hot water and detergent.

Additionally, avoid reinfection by throwing out or cleaning items such as eyeglass cases, eye and face makeup, and contact lenses.

When To See a Healthcare Provider For Pink Eye

For some cases of pink eye, it may be important to see a healthcare provider. A primary care physician (PCP) can treat most pink eye cases. However, you may be referred to an ophthalmologist or allergist for evaluation based on symptoms, severity, and response to treatment. A pediatrician should evaluate children to determine the cause of symptoms and appropriate treatment.

Per the CDC, seek medical attention for:

  • Intense eye redness
  • Eye pain
  • Symptoms that do not improve with treatment
  • Sensitivity to light
  • Blurred vision that persists after clearning eye secretions

Other situations that may warrant immediate medical attention, per MedlinePlus, are symptoms that last more than three to four days, swelling of the eyelids or area surrounding the eye, and the presence of a headache with your symptoms.

Newborns with pink eye require immediate medical care, the CDC says. Babies exposed to bacteria during vaginal birth require antibiotics to clear the infection. Without treatment, conjunctivitis caused by gonorrhea can lead to vision complications.

Further, anyone with a weakened immune system due to HIV, cancer treatment, or other medical conditions or treatments should seek treatment for pink eye.

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