Yes, it can work. Conjunctivitis, the so called pink eye, refers to infections of conjunctiva which is the clear layer. Conjunctivitis might be caused by bacterial, viral or allergic infection. The common symptoms of conjunctivitis include sensitivity to light, redness of eye, dry eye, stinging, eyelids swelling and foreign body sensation. In some cases, the infections could heal up without requirement of any treatment. For example, allergic conjunctivitis, can recover very soon if the patients are get out of touch with the allergens. As to bacterial or viral caused infection, oil of oregano can effectively help people by controlling the infection. It contains some anti-inflammatory agents which can alleviate swelling and irritations. It really works, yet you should consult with your doctor on how to use it and the proper dosage. Direct application to eyes might worsen the problem. There is something much easier and safer than the oil of oregano. You can use some salt water to wash your eyes and as warm compress. Normally warm compress can effectively help pink eye.