04/20/2026
Pink eye and allergic conjunctivitis can look similar, but the causes and treatments are very different. Cleveland Clinic breaks down the key differences below.
Pink eye is a contagious infection caused by an organism or a germ, like a:
Virus
Bacterium
Fungus
Parasite
You can get pink eye when you come into contact with someone who has it or you rub your eyes after touching a contaminated surface.
Allergic conjunctivitis isn’t contagious, and you can experience it year-round. It’s triggered when your eyes come into direct contact with allergens. Products that commonly cause contact dermatitis (like certain soaps, detergents, or moisturizers) can also cause an allergic eye reaction.
Pink eye usually starts in one eye before spreading to the other, while allergic conjunctivitis can affect one or both eyes at the same time. Pink eye can sometimes be connected to more than one respiratory infection symptom, like coughing, sneezing, runny nose, fever and sore throat. But allergic conjunctivitis usually has a simpler association with sneezing and a runny nose. In general, allergic conjunctivitis is paired with marked itching, redness and watery discharge, whereas infectious conjunctivitis has discomfort, chronic discharge and less itching.
Infectious conjunctivitis often improves within five to 10 days with no treatment at all or with simple drops like artificial tears. But it can still be very uncomfortable. If you have worsening symptoms after more than two days, making an appointment to determine if prescription eye drops are more appropriate.
Allergic conjunctivitis often gets better when you limit your interactions with the allergen that’s causing eye inflammation. But symptoms can linger for many weeks with seasonal changes that come in the spring and fall, requiring a prescription steroid eyedrop to break the cycle of itching and inflammation.
The bottom line: Neither of these conditions is sight-threatening. But it’s always best to seek an opinion from an eye doctor if you’re unable to treat symptoms adequately at home after a couple days, especially if you’re experiencing worsening vision or light sensitivity.
