Conjunctivitis (Pink Eye)

Conjunctivitis, commonly called "pink eye," is inflammation of the conjunctiva—the clear membrane covering the white of the eye and lining the inner eyelids. It's one of the most common eye conditions and has several different causes, each requiring different management.

What Are the Different Types of Conjunctivitis?

There are seven main types of conjunctivitis, each with different causes, symptoms, and treatments. The three most common are viral, bacterial, and allergic. The type determines whether the condition is contagious and what treatment is needed. For a patient-friendly comparison of the three main types, see our guide on bacterial vs viral vs allergic pink eye.

At a Glance: Conjunctivitis Types Compared

Type	Key Symptoms	Cause	Contagious?	Typical Treatment	Duration
Viral	Watery discharge, redness, cold symptoms	Adenovirus, other viruses	Yes — highly	Supportive care (cold compresses, artificial tears)	1–3 weeks
Bacterial	Thick yellow-green discharge, crusting	Staph, Strep, Haemophilus	Yes	Antibiotic eye drops	5–7 days with treatment
Allergic	Intense itching, watery eyes, puffiness	Pollen, dust, pet dander	No	Antihistamine drops, allergen avoidance	While exposed to allergen
GPC	Itching, mucus, lens intolerance	Contact lens wear	No	Lens modification, anti-inflammatory drops	Weeks to months
Gonococcal	Copious pus, severe swelling	N. gonorrhoeae (STI)	Yes	Emergency systemic antibiotics	Days with urgent treatment
Chlamydial	Chronic redness, mild discharge	C. trachomatis (STI)	Yes	Oral antibiotics	Weeks
Neonatal	Discharge in newborn (first 28 days)	Various (depends on timing)	Varies	Depends on cause — may be emergency	Varies

Viral Conjunctivitis

Most common type:

• Highly contagious; often starts in one eye and spreads to the other
• Watery discharge, frequently linked to a recent cold
• Resolves on its own in 1–2 weeks without antibiotics
• In rare cases, influenza viruses including H5N1 (bird flu) can cause conjunctivitis — see our guide on pink eye and bird flu

Learn more about viral conjunctivitis.

Bacterial Conjunctivitis

• Thick, yellow-green discharge that often "glues" eyelids shut overnight
• Moderately contagious
• May respond faster with antibiotic drops, though mild cases can self-resolve

Learn more about bacterial conjunctivitis.

Allergic Conjunctivitis

• Not contagious—triggered by allergens such as pollen, dust, or pet dander
• Intense itching is the hallmark symptom
• Usually affects both eyes and often accompanies sneezing or congestion

Not sure if your symptoms are from allergies or an infection? See our guide on pink eye vs allergies. Learn more about allergic conjunctivitis.

Giant Papillary Conjunctivitis

• Most commonly triggered by contact lens wear
• Characterized by large bumps (papillae) under the upper eyelid
• Treatment centers on changing or discontinuing lens use

Learn more about giant papillary conjunctivitis.

Gonococcal Conjunctivitis

• Considered an ocular emergency—can threaten vision within 24–48 hours
• Causes severe, purulent discharge
• Requires systemic antibiotics and urgent ophthalmologic care

Learn more about gonococcal conjunctivitis.

Chlamydial Conjunctivitis

• Chronic, often mild redness that may persist for weeks if untreated
• Requires oral antibiotics (topical treatment alone is insufficient)
• Sexual partners need concurrent treatment to prevent reinfection

Learn more about chlamydial conjunctivitis.

Neonatal Conjunctivitis

• Occurs in newborns within the first month of life; timing of onset helps guide diagnosis
• Erythromycin ointment is given at birth as prophylaxis
• Any eye discharge in a newborn warrants urgent evaluation

Learn more about neonatal conjunctivitis.

What Are the Symptoms of Conjunctivitis?

The most common symptoms of pink eye include redness, discharge, and irritation. The specific type of discharge—watery, thick, or stringy—helps distinguish between viral, bacterial, and allergic conjunctivitis.

• Red or pink appearance
• Eye irritation or discomfort
• Tearing
• Discharge (varies by type)
• Swelling of conjunctiva or eyelids

How Is Conjunctivitis Diagnosed?

Conjunctivitis is usually diagnosed through a clinical examination based on your symptoms, the type of discharge, and your medical history. Most cases do not require laboratory testing, but cultures may be taken for severe or atypical presentations.

Clinical Examination

• Assessment of discharge type
• Evaluation of conjunctiva
• Check for lymph node swelling
• Vision testing
• Slit-lamp examination if needed

When Testing May Be Done

• Severe or atypical cases
• Not responding to treatment
• Suspected gonococcal or chlamydial infection
• Neonatal conjunctivitis

How Is Conjunctivitis Treated?

Treatment depends on the type of conjunctivitis. Most cases can be managed with cool compresses, artificial tears, and good hygiene. Bacterial forms may need antibiotic drops, while allergic conjunctivitis responds to antihistamine drops and allergen avoidance.

Artificial tears help keep the eye lubricated, and careful hand hygiene prevents spread. For evidence-based home care strategies, see our guide on pink eye home remedies. Serious types like gonococcal or neonatal conjunctivitis need prompt, specialized treatment. Contact lens wearers should stop wearing lenses until the condition fully resolves.

If symptoms do not improve within a week, or if you experience significant pain or vision changes, see an eye doctor for evaluation.

For detailed treatment information, see the pages for viral, bacterial, allergic, gonococcal, chlamydial, and neonatal conjunctivitis.

How Can You Prevent Conjunctivitis?

The best ways to prevent conjunctivitis are frequent handwashing, avoiding touching your eyes, and not sharing personal items like towels or eye makeup. During an active infection, strict hygiene prevents spreading it to others.

• Wash hands frequently and avoid touching or rubbing your eyes
• Don't share towels, pillows, or eye makeup
• Change pillowcases daily during an active infection
• Discard eye makeup used while infected
• Stay home while contagious (viral: 10–14 days; bacterial: 24–48 hours after starting antibiotics)
• Contact lens wearers should stop lens use during infection and discard affected lenses and cases

For details on contagiousness and return-to-work/school guidelines, see our guide on is pink eye contagious?. For information on how long pink eye lasts by type, see our duration guide. Parents can find school policies and child-specific advice in our guide on pink eye in children.

For comprehensive prevention and hygiene guidance—especially around infectious spread—see viral conjunctivitis.

When Should You See a Doctor for Conjunctivitis?

Most mild cases of pink eye improve on their own within a week, but certain symptoms require prompt medical evaluation. See a doctor if you experience significant pain, vision changes, or symptoms that are not improving. Keep in mind that not every red eye is pink eye — several other conditions can look similar. See our guide on conditions mistaken for pink eye.

Frequently Asked Questions

How can I tell if it's viral or bacterial?

Viral: watery discharge, one eye first, often with cold symptoms, may have swollen lymph node by ear. Bacterial: thick yellow-green discharge, lids stuck shut in morning. However, distinguishing can be difficult, and some cases need professional evaluation.

Do I need antibiotics?

Viral conjunctivitis doesn't respond to antibiotics—it needs to run its course. Bacterial conjunctivitis may resolve on its own, but antibiotics can speed recovery and reduce contagiousness. Allergic conjunctivitis needs allergy treatment, not antibiotics.

How long am I contagious?

Viral: typically 10-14 days from symptom onset. Bacterial: until 24-48 hours after starting antibiotic drops, or about 5-7 days if untreated. Allergic conjunctivitis is not contagious.

Can I go to work or school?

With viral or bacterial conjunctivitis, it's best to stay home while symptomatic and contagious. Children should stay home from school. Allergic conjunctivitis is not contagious, so isolation isn't needed.

Should I throw away my makeup?

Yes, discard any eye makeup (mascara, eyeliner) used during the infection, as it can harbor bacteria or viruses and cause reinfection.

Why do I keep getting conjunctivitis?

Recurrent conjunctivitis may be due to allergies (seasonal patterns), underlying eyelid conditions (blepharitis), chronic dry eye, or environmental factors. See an eye doctor if conjunctivitis keeps returning. For a detailed look at causes and solutions, see our guide on recurring pink eye.

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