Pink Eye vs Allergies: How to Tell the Difference

Pink eye (or conjunctivitis) makes your eyes red, irritated, and uncomfortable. Allergies can also cause eye irritation and turn the whites of your eyes a pink or red color.

This is called allergic conjunctivitis since an allergic reaction triggers eye inflammation. 

If you think you have pink eye but you also experience allergies, it can be challenging to know what you’re truly dealing with.

In this article, I’ll discuss the differences between pink eye and allergies, including their symptoms, causes, and how contagious each is.

Then I’ll explain how pink eye and allergies are diagnosed and the best treatments for each so you can find relief.

Common Symptoms

Pink eye and allergies can have the same symptoms, including:

• Redness of the eyes
• Itchy eyes
• Blurred vision
• Grittiness and/or crust on the eyelids
• Eye pain
• Tearing of the eyes
• Sensitivity to light

Additionally, some symptoms are typically exclusive to each.

Pink eye

Bacterial conjunctivitis may:

• Cause large amounts of discharge that can cause eyelids to stick together
• Occur alongside an ear infection

Whereas viral conjunctivitis typically: 

• Causes watery discharge from the eye
• Begins in one eye and spreads to the other after a couple of days
• Occurs alongside cold and/or flu symptoms

Allergies

Allergic conjunctivitis typically: 

• Occurs in both eyes
• Occurs alongside other allergy symptoms like itchy nose, runny nose, and sneezing
• Causes intense itching and tearing of the eyes
• Causes swelling of the eyes

Causes

While pink eye and allergies present similarly, they are caused by different things. 

Pink eye

What most people think of as pink eye can be a bacteria infection or a viral infection.

• Bacterial conjunctivitis is caused by bacteria entering the eye, either through person-to-person contact or when someone touches a contaminated surface and then touches their eye. Common organisms associated with bacterial conjunctivitis include Staphylococcus aureus, Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis.

• Viral conjunctivitis can be caused by several different types of viruses, most often adenoviruses. These fast-spreading viruses typically spread through hand-to-eye contact after touching an infected surface. These viruses can spread through tears, fecal matter, eye discharge, and respiratory discharge such as when coughing and sneezing.

Allergies

Allergic pink eye occurs when the body reacts to a foreign substance (called an allergen) that the body thinks is harmful.

The immune system kicks in to fight off the allergen, in turn triggering an allergic reaction that may cause eye inflammation.

Common allergens include mold, animal dander, pollen, and dust.

How Contagious Are They?

Allergies are not contagious, but pink eye is.

Viral pink eye is more common and contagious than bacterial pink eye, but both can spread through personal contact or hand-to-eye contact.

To prevent infection, wash your hands regularly, especially if someone around you has pink eye.

Also keep your hands away from your eyes as much as possible. 

Diagnosis

Because pink eye and allergies can present similarly, you’ll likely have to see a doctor or medical specialist to determine which you are dealing with. 

Your doctor will examine your eyes and may swab the eye to get a sample for analysis.

They will also ask questions about your symptoms and overall health.

Treating Pink Eye

The same home remedies may help treat bacterial and viral conjunctivitis, but each requires different medication.

Home remedies

Home remedies for pink eye include:

• A warm compress on the eye(s)
• Over-the-counter (OTC) lubricating eye drops
• Not wearing contact lenses or makeup until the infection clears

Medications

OTC painkillers such as ibuprofen (Advil) can help with discomfort from pink eye.

Bacterial conjunctivitis often goes away in 2-5 days without treatment (although it can take up to two weeks).

However, your doctor may prescribe antibiotics (usually eye drops) if they believe you are dealing with a certain type of bacteria, you are immunocompromised, or if you have lots of eye discharge.

Antibiotics are ineffective for viral conjunctivitis.

Viral pink eye typically goes away on its own after 7-14 days without treatment (although it can take up to three weeks).

Your doctor may prescribe an antiviral medication if they believe your case is serious. (For example, if it is caused by the herpes simplex virus.) 

Treating Allergies

The best way to treat allergies is to prevent them in the first place by avoiding triggers.

However, since this is not always possible, home remedies and medications can help ease symptoms.

Home remedies

Home remedies for allergic conjunctivitis include:

• A cool compress on the eye(s)
• OTC lubricating eye drops

Medications

Your doctor may prescribe allergy medication, eye drops, or a combination of medications.

If you still have symptoms, they may recommend immunotherapy (allergy shots).

How K Health Can Help

Did you know you can get affordable primary care with the K Health app?

Download K Health to check your symptoms, explore conditions and treatments, and if needed text with a clinician in minutes. K Health’s AI-powered app is based on 20 years of clinical data.