With allergy season still lingering in late spring and summer, itchy, red, and watery eyes are a common complaint for patients of all ages. But how can you tell whether it’s just allergic conjunctivitis—or something more serious like a bacterial or viral eye infection?
The symptoms can look similar, but the treatment and urgency are very different. Misdiagnosing the cause can lead to delayed relief or even long-term damage. Below, our ophthalmologists explain the key differences, treatment options, and when it’s time to schedule an eye exam.
What Is Conjunctivitis?
Conjunctivitis, commonly known as “pink eye,” is an inflammation of the conjunctiva — the thin, clear tissue that lines the inside of the eyelid and covers the white of the eye.
There are three main types of conjunctivitis:
- Allergic conjunctivitis – triggered by allergens like pollen, pet dander, or dust
- Bacterial conjunctivitis – caused by bacterial infections
- Viral conjunctivitis – caused by viruses, often alongside a cold or respiratory illness
Each type has unique signs and treatment needs.
Allergic Conjunctivitis
Allergic conjunctivitis is not contagious. It often affects both eyes and is linked to environmental allergens that trigger a histamine response, leading to inflammation and discomfort.
Common symptoms:
- Itchy eyes (often intense)
- Redness in both eyes
- Watery or stringy clear discharge
- Swollen eyelids
- Sneezing or nasal congestion (if seasonal allergies are involved)
- Symptoms improve indoors or with allergy medication
Who’s most affected:
- Children and adults with seasonal or environmental allergies
- Contact lens wearers may experience worse symptoms due to irritation
Bacterial Conjunctivitis
This form of pink eye is caused by bacteria and is highly contagious—especially among children and those in close-contact settings like schools or daycare centers.
Common symptoms:
- Redness in one or both eyes
- Thick yellow, green, or white discharge
- Eyelids crusted shut in the morning
- Mild pain or discomfort
- Swelling of the eyelids
- May spread rapidly between individuals
When antibiotics are needed:
A short course of antibiotic eye drops or ointment is typically prescribed. These are effective at clearing up the infection quickly and preventing further spread.
Viral Conjunctivitis
Often associated with the common cold or flu, viral conjunctivitis usually starts in one eye and may spread to the other. It is also highly contagious, and unfortunately, it does not respond to antibiotics.
Common symptoms:
- Watery discharge (more than allergic conjunctivitis)
- Red, irritated eyes
- Gritty sensation, as if something is in the eye
- Swollen, tender lymph nodes (in some cases)
- Accompanied by a sore throat or upper respiratory infection
Treatment:
Viral conjunctivitis resolves on its own within 1 to 2 weeks. Cold compresses and lubricating eye drops can help relieve discomfort. Good hygiene is essential to avoid spreading the virus.
Antihistamines vs. Antibiotics: When Each Helps
Antihistamines:
- Effective for itchy, allergic eyes
- Available as oral medications or antihistamine eye drops
- Best when symptoms are triggered by known allergens (e.g., pollen, pets)
Antibiotics:
- Prescribed only for bacterial conjunctivitis
- Not effective against allergies or viral infections
- Should only be used when prescribed by an eye care provider — improper use can lead to antibiotic resistance or irritation
Red Flags: When to Worry
Certain symptoms suggest that it’s not just allergies — and you should call your ophthalmologist right away.
Warning signs to watch for:
- Thick, yellow/green mucus-like discharge
- Eyelids stuck shut in the morning
- Eye pain or sensitivity to light
- Blurred vision that doesn’t improve with blinking
- One-sided symptoms that worsen over time
- No improvement after using allergy medication
- Recent exposure to someone with pink eye
When to Call Your Ophthalmologist
If you or your child are experiencing persistent eye redness, unusual discharge, eye pain, or vision changes, it’s time to consult an ophthalmologist. An eye exam can determine the underlying cause and ensure you receive the proper treatment — whether it’s allergy relief, antiviral management, or antibiotics.
At North Fulton Eye Center, our board-certified ophthalmologists are trained to identify subtle differences between allergies and infections, ensuring your eyes receive the care they need.
Proactive Tips for Eye Health During Allergy Season
- Wear sunglasses outdoors to protect eyes from airborne allergens
- Wash hands frequently and avoid touching your eyes
- Use allergen-reducing air filters indoors
- Remove contact lenses at the first sign of irritation
- Replace eye makeup frequently to avoid bacterial buildup
Still Not Sure If It’s Allergies or an Infection?
Let our experts help. Schedule an eye exam at North Fulton Eye Center to get a precise diagnosis and fast, effective relief. Don’t let eye discomfort linger this summer.