Pink Eye (Conjunctivitis) in Children: Viral, Bacterial, and Allergic — What's the Difference?
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This health information is reviewed by board-certified pediatricians and follows current American Academy of Pediatrics (AAP) guidelines.
Pink eye — the medical term is conjunctivitis — is one of the most common reasons families across Robbinsville, Hamilton, Plainsboro, and Mercer County call our office. The eye is red, there's often discharge, and the eyelid may be swollen. It can look the same whether the cause is viral, bacterial, or allergic — but the treatment and contagion rules are very different for each type.
At Hummingbird Pediatrics, we want to help you tell them apart so you can make the right call about treatment, school, and when to come in.
The Three Types of Conjunctivitis
Viral Pink Eye
Viral conjunctivitis is the most common type and is usually caused by the same viruses responsible for colds and upper respiratory infections.
- Watery or mucousy (not thick or pus-like) discharge
- Often affects one eye first, then spreads to the other
- Frequently accompanied by a runny nose, sore throat, or other cold symptoms
- The eye may be pink and irritated with some crusting in the morning
- Usually resolves on its own within 7 to 10 days
Antibiotic eye drops do NOT treat viral conjunctivitis. This type has to run its course.
Bacterial Pink Eye
Bacterial conjunctivitis is caused by bacteria and is more likely to require antibiotic drops.
- Thick, yellow-green discharge that accumulates throughout the day
- Eyelids that stick together, especially after sleep
- Can affect one or both eyes
- May not be accompanied by cold symptoms
- Does not usually improve without treatment
If your child has thick discharge and sticky eyelids, call our office — antibiotic eye drops often resolve bacterial pink eye significantly faster.
Allergic Conjunctivitis
Allergic conjunctivitis is triggered by pollen, pet dander, dust mites, or other allergens — it is not contagious.
- Intense itching is the hallmark symptom (less common in viral or bacterial)
- Both eyes are almost always affected at the same time
- Watery discharge
- Often associated with other allergy symptoms: sneezing, runny nose, nasal congestion
- Worse outdoors or during high-pollen periods, better indoors with air conditioning
Antibiotic drops are not helpful for allergic conjunctivitis. Antihistamine eye drops (available over the counter) provide targeted relief.
Contagion and School Return
Viral and bacterial conjunctivitis are both contagious through direct contact with discharge and contaminated surfaces.
- Viral: Contagious as long as symptoms are present. Most schools require keeping children home while significant discharge is active.
- Bacterial: Contagious until treatment has been started for at least 24 hours and symptoms are improving.
- Allergic: Not contagious at all. Children can attend school as usual.
Home Care for Pink Eye
For all types: - Gently clean discharge from the eyelids using a clean, damp cloth or cotton ball — wipe from the inner corner of the eye outward, using a fresh wipe for each pass - Wash hands frequently and avoid sharing towels, pillowcases, or face cloths - Cool or warm compresses over the closed eye can provide comfort
For viral: - No specific treatment is needed. Keep the eye clean and comfortable.
For bacterial: - Prescription antibiotic eye drops or ointment from your pediatrician speed recovery significantly. Call our office.
For allergic: - Over-the-counter antihistamine eye drops work well for most children with allergic conjunctivitis - Oral antihistamines may also help if nasal allergy symptoms are present alongside eye symptoms - Reducing allergen exposure (keeping windows closed, showering after outdoor play) helps as well
When to Call Hummingbird Pediatrics
- Your child has thick yellow or green discharge suggesting bacterial conjunctivitis
- Pink eye is accompanied by significant eye pain, sensitivity to light, or vision changes
- A newborn or very young infant has any eye discharge
- Symptoms are getting worse rather than improving after several days
- You're not sure which type it is
Go to the emergency room if your child has significant eye pain, vision changes, or eyelids that are severely swollen and red (which may suggest periorbital cellulitis, a more serious infection).
Spring is peak season for both viral illness and allergy symptoms — making pink eye especially common from March through May. If you're not sure what type your child has, give us a call. We can usually help you figure it out over the phone, and if we need to take a look, we'll get your child in quickly.
Frequently Asked Questions
How can I tell if my child's pink eye is bacterial or viral?
Bacterial pink eye typically produces thick yellow or green discharge that causes the eyelids to stick together, especially in the morning. Viral pink eye usually has watery or light discharge and often comes alongside a cold, runny nose, or sore throat. Allergic conjunctivitis causes itchy, watery eyes in both eyes and often accompanies sneezing or a runny nose. Only your pediatrician can definitively determine the type — if you are unsure, give us a call and we can often help you figure it out over the phone.
Does my child need antibiotic eye drops for pink eye?
Not always — and most pink eye does not require antibiotic drops. Viral pink eye, which is the most common type, is not treated with antibiotics and resolves on its own in 7–10 days. Antibiotic drops are prescribed for confirmed or likely bacterial conjunctivitis. Allergic conjunctivitis is treated with antihistamine drops or other allergy management. Your pediatrician will recommend the appropriate treatment based on the likely cause.
When can my child go back to school after pink eye?
It depends on the type. For bacterial pink eye, most schools allow children to return after 24 hours of antibiotic drops and once discharge is no longer excessive. Viral pink eye is more nuanced — children can often return once they feel well enough and do not have significant discharge, though practices vary by school. Allergic conjunctivitis is not contagious, so there is no reason to stay home. Ask your child's school about their specific policy if you are unsure.
How do I prevent pink eye from spreading in my household?
Wash hands frequently, especially after touching your child's face or applying eye drops. Do not share towels, pillowcases, or washcloths. Change your child's pillowcase daily while they are symptomatic. Wash hands before and after applying any eye drops or ointment. Avoid touching your own eyes after contact with your child. Launder any shared linens in hot water. Pink eye spreads easily, but these measures significantly reduce transmission to siblings and other household members.
My child's eye looks red but there's no discharge — is it pink eye?
Not necessarily. Red eyes in children have many causes beyond conjunctivitis, including a broken blood vessel (subconjunctival hemorrhage), a foreign body in the eye, dry eyes, allergies, or irritation from smoke, chlorine, or dust. If there is no discharge and your child has no other symptoms, it may not be infectious pink eye at all. If the redness is accompanied by eye pain, sensitivity to light, or vision changes, see your pediatrician promptly as these can signal a more serious condition.
Need Personal Guidance?
This article provides general information. For questions specific to your child's health, please call our office or book an appointment online.