What eye drops should I use for pink eye?

There are three main types of conjunctivitis, or “pink eye,” as it is commonly known: viral, bacterial, and allergic, and this post focuses on the best eye drops, or treatment, for each.

Pink eye can be due to viruses, bacteria, or allergies.

Pink eye can be due to viruses, bacteria, or allergies.

Viral Pink Eye

Caused by the same viruses that can also cause the common cold — most commonly, adenovirus — viral pink eye can be a real bugger. Importantly, there are no good eye drops for treating viral pink eye.

Antibiotic eye drops won’t work, since those treat bacteria. And “get the red out” eye drops like Visine are no good either, because your eye will quickly become habituated to the tetrahydrozoline in the Visine. Tetrahydrozoline (and naphazoline, the ingredient in other, similar eye drops) are vasoconstrictors, which cause the blood vessels on the surface of the eye to constrict, so the eye appears less pink.

Sounds great, right? Well, the problem is those blood vessels become “addicted” to the medication, and when you stop using the Visine a couple of days later, you get rebound hyperemia — the blood vessels, now deprived of the medication, swell to larger than ever, making your eyes even more red and irritated than before. Visine, or other “red eye” eye drops, are never a good idea.

Bacterial Pink Eye

Fortunately, for pink eye that is caused by a bacterial infection, there are many wonderful options for eye drops. If your doctor diagnoses bacterial conjunctivitis, he or she may prescribe eye drops such as ofloxacin or polytrim, or an ointment like erythromycin. True bacterial conjunctivitis should resolve within a day or two of starting antibiotic eye drops. If it doesn’t, it’s likely not bacterial.

Allergic Pink Eye

Pink eye that is accompanied by itchy, watery eyes is often due to allergies to something in the environment. It’s easy to treat with over-the-counter ketotifen eye drops. Cold compresses can help too. Oral antihistamines can also be helpful.

For more information about pink eye, including signs and symptoms, as well as red flags, read this article.