Conjunctivitis may be caused by allergies to animals, chemicals, or other irritants. This includes eye drops. Most eye drops contain chemicals (preservatives) that may irritate your eyes. The problem can keep coming back. This can lead to an eye infection. Treatment involves relieving your symptoms and avoiding the irritant. If you have an infection, it will be treated.
Allergies
Grass, pollen, dust, mold, and animals are common causes of allergies. They can make your eyes red, watery, and itchy. In most cases, both eyes are affected.
Treatment
The best way to control an allergy is to avoid its source. Cold compresses and eye drops can help reduce the swelling. They can also help relieve redness and itching. Don't rub your eyes. If your allergy is severe, your health care provider may prescribe eye drops or oral medicines. Be certain to use the eye drops or take the medicine as prescribed. Symptoms may take several weeks to clear up.
Other irritants
Pollution, smoke, contact lenses, and makeup can also irritate your eyes. Your eyes can get red, sore, puffy, and watery. One or both eyes may become irritated.
Treatment
The best thing to do is avoid the irritant. Artificial tears can help flush out the eye and lubricate the surface. Your health care provider may also prescribe eye drops to reduce swelling and relieve redness. Be certain to use the eye drops as prescribed. In some cases, you may have to stop wearing contact lenses or certain types of eye makeup.
Online Medical Reviewer: Daphne Pierce-Smith RN MSN
Online Medical Reviewer: Mahammad Juber MD
Online Medical Reviewer: Raymond Turley Jr PA-C
Date Last Reviewed: 03/01/2025
© 2000-2026 The StayWell Company, LLC. All rights reserved. This information is not intended as a substitute for professional medical care. Always follow your healthcare professional's instructions.
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