Your eyes are itchy and you’re in serious need of relief. You find an old bottle of eye drops in your medicine cabinet. You pause before using them and wonder, should I be using them?When should I not use eye drops? The first thing you should do is make sure they aren’t prescription eye drops. Those are geared towards curing specific conditions, not just moistening the eyes. Second, it’s not a good idea to use eye drops that are more than a month old. The preservatives that keep them sterile only last for about 28 days, and should definitely be disposed of after three months. After that, you run the risk of inflammation, irritation, or even infection because bacteria may get into the drops. If you need the drops for medical purposes, they may not be as effective in treating any eye condition you may have. Also, don’t use someone else’s eye drops, especially if they are prescription drops. As mentioned above, prescription drops are designed to treat specific ailments. On top of that, you also run the risk of spreading infections between the two of you. Even if they aren’t old or medicated eye drops, the drops you have may not be good for your needs. For example, your itchiness may be caused by allergies. If so, try to avoid over-the-counter allergy drops, as their antihistamine effects can dry your eyes out more, CEENTA Ophthalmologist Ernest Bhend, MD, said. Instead, use artificial tears, or even prescription allergy eye drops. Since a lot of allergy symptoms can actually be caused by dry eye, artificial tears will not only moisten your eyes but can also help flush out the allergens. You also want to avoid eye drops that are designed to “get the red out,” Dr. Bhend said. “These drops work just by constricting the blood vessels on the surface of the eyes,” he said. “These vasoconstrictors can actually irritate the eyes more. Regular artificial tears are a better option.” It’s also best to avoid putting too many drops in your eyes. It's sometimes easier said than done, because getting drops into your eyes in the first place is tricky and it’s easy to put too many in to overcompensate. Still, this is something you want to not do because you not only run the risk of wasting drops, but in some cases too many medicated eye drops can irritate your eyes. And no matter how itchy your eyes are, don’t rub them. You’ll only irritate your eyes more and make the itching worse. If the drops you found are new and are good for your particular needs, it’s probably fine to use them. But if you have any doubts, play it safe and just buy a new bottle. This blog is for informational purposes only. For specific medical questions, please consult your physician. To make an appointment with a CEENTA eye doctor, call 704-295-3000. You can also schedule an appointment online or through myCEENTAchart.