Pink Eye (Conjunctivitis): Causes, Symptoms, and Treatment

What is Pink Eye (Conjunctivitis)?

Pink eye, medically known as conjunctivitis, is an inflammation or infection of the transparent membrane (conjunctiva) that lines your eyelid and covers the white part of your eyeball. When small blood vessels in the conjunctiva become inflamed, they're more visible. This is what causes the whites of your eyes to appear reddish or pink.

Pink eye is commonly caused by a bacterial or viral infection, an allergic reaction, or — in babies — an incompletely opened tear duct. Though pink eye can be irritating, it rarely affects your vision. Treatments can help ease the discomfort of pink eye. Because pink eye can be contagious, early diagnosis and treatment can help limit its spread.

Source: Mayo Clinic

Common Causes

The most common causes of pink eye include:

• Viruses: The most common cause of pink eye is the same virus responsible for the common cold. This type of pink eye is highly contagious.
• Bacteria: Bacterial infections, such as those caused by Staphylococcus aureus or Streptococcus pneumoniae, can lead to pink eye. This form is also contagious.
• Allergies: Allergic reactions to pollen, dust mites, pet dander, or other allergens can cause allergic conjunctivitis, which is not contagious.
• Irritants: Exposure to irritants like smoke, chlorine in swimming pools, or airborne pollutants can cause irritant conjunctivitis.
• Contact lens wear: Improper use or cleaning of contact lenses can lead to bacterial or fungal infections, causing pink eye.
• Foreign objects: Dust, dirt, or other foreign particles in the eye can irritate the conjunctiva.
• Chemical exposure: Splashes of household cleaners or other chemicals can cause chemical conjunctivitis, which requires immediate medical attention.
• Sexually transmitted infections (STIs): Certain STIs, like chlamydia or gonorrhea, can cause conjunctivitis in newborns during childbirth or in adults through contact.
• Autoimmune conditions: Rarely, conditions like rheumatoid arthritis or lupus can cause conjunctivitis.
• Blocked tear ducts: In newborns, a blocked tear duct can lead to pink eye.

Source: Centers for Disease Control and Prevention (CDC)

Associated Symptoms

The symptoms of pink eye can vary depending on the cause but often include:

• Redness in one or both eyes
• Itchiness in one or both eyes
• A gritty feeling in one or both eyes
• A discharge in one or both eyes that forms a crust during the night and may prevent your eye or eyes from opening in the morning
• Tearing
• Sensitivity to light (photophobia)
• Swollen eyelids
• Blurred vision (in some cases)
• Burning sensation in the eyes

In cases caused by allergies, you may also experience sneezing, itching, or a runny nose. If caused by a bacterial or viral infection, you might have symptoms of a cold, flu, or respiratory infection.

Source: NHS

When to See a Doctor

You should see a doctor if you experience any of the following:

• Severe pain in the eye(s)
• Sensitivity to light or blurred vision that does not improve when discharge is wiped from the eye(s)
• Intense redness in the eye(s)
• Symptoms that worsen or do not improve, including if pink eye symptoms persist for more than a week
• A weakened immune system due to HIV, cancer treatment, or other medical conditions
• Pre-existing eye conditions that may put you at risk for complications
• Recurrent episodes of conjunctivitis

Newborns with symptoms of pink eye should be seen by a doctor immediately, as it could be a sign of a serious infection.

Source: American Academy of Ophthalmology

Diagnosis

Your doctor can often determine whether you have pink eye by asking about your symptoms and recent health history. An examination of the eye may also be performed. In some cases, your doctor may:

• Take a sample of the discharge from your eye for laboratory analysis to determine the cause (bacterial, viral, or allergic).
• Recommend an allergy test if allergic conjunctivitis is suspected.
• Perform a slit-lamp examination to look more closely at the structures of the eye.

In most cases, no specific testing is needed, and the diagnosis is made based on symptoms and examination alone.

Source: Mayo Clinic

Treatment Options

The treatment for pink eye depends on the cause:

Viral Conjunctivitis

Viral conjunctivitis often does not require medical treatment and will clear up on its own within a few days to two weeks. To relieve symptoms, you can:

• Apply a cold, wet washcloth to your eyes several times a day.
• Use over-the-counter artificial tears or lubricating eye drops.
• Avoid touching or rubbing your eyes.
• Wash your hands frequently.

Antibiotics will not help viral conjunctivitis.

Bacterial Conjunctivitis

If your pink eye is caused by bacteria, your doctor may prescribe antibiotic eye drops or ointments. Symptoms typically improve within a few days of starting treatment. It is important to complete the full course of antibiotics as prescribed.

Allergic Conjunctivitis

For allergic conjunctivitis, treatment focuses on relieving symptoms. This may include:

• Over-the-counter or prescription allergy medications (antihistamines).
• Anti-inflammatory or anti-allergic eye drops.
• Avoiding known allergens.
• Applying a cool compress to the eyes.

Irritant Conjunctivitis

If caused by an irritant, rinsing the eye with saline solution or artificial tears can help flush out the irritant. Avoid further exposure to the irritant.

Home Remedies

Regardless of the cause, the following home remedies can help relieve symptoms:

• Use a clean, warm or cold compress on your eyes to reduce swelling and discomfort.
• Avoid wearing contact lenses until your symptoms clear up.
• Do not share towels, washcloths, or pillows.
• Wash your hands frequently and avoid touching your eyes.
• Use over-the-counter lubricating eye drops (artificial tears).

Source: CDC

Prevention Tips

To prevent the spread of pink eye, follow these tips:

• Wash your hands frequently with soap and warm water. If soap and water are not available, use an alcohol-based hand sanitizer.
• Avoid touching or rubbing your eyes.
• Do not share personal items such as towels, washcloths, pillowcases, makeup, or eye drops.
• Clean and disinfect surfaces like countertops, doorknobs, and bathroom fixtures regularly.
• If you wear contact lenses, follow your eye doctor’s instructions for cleaning and replacing them. Never share contact lenses or cases with others.
• Avoid swimming in pools if you or someone else has pink eye.
• If you have allergic conjunctivitis, avoid allergens that trigger your symptoms.
• Use goggles when swimming to protect your eyes from bacteria and chemicals in the water.

If you or your child has pink eye, stay home from work, school, or daycare until symptoms improve to avoid spreading the infection to others.

Source: CDC

Emergency Warning Signs

Seek immediate medical attention if you experience any of the following symptoms, as they may indicate a more serious condition:

• Severe pain in the eye(s), which could indicate a more serious issue like glaucoma or an infection deeper within the eye.
• Extreme sensitivity to light (photophobia), which may suggest inflammation inside the eye (uveitis) or other serious conditions.
• Blurred vision or loss of vision that does not improve when discharge is wiped away.
• Intense redness in the eye(s), especially if it is accompanied by pain or vision changes.
• Symptoms of a severe allergic reaction, such as difficulty breathing, swelling of the face or throat, or a rapid heartbeat.
• Signs of a systemic infection, such as fever, chills, or body aches, which may indicate a more widespread infection.
• A foreign object embedded in the eye or a chemical splash, which requires immediate medical evaluation.
• Symptoms that worsen rapidly or do not improve with treatment.

If you experience any of these symptoms, go to the nearest emergency room or call emergency services immediately.

Source: American Academy of Ophthalmology