The eye drops have a shelf life of about four weeks.
Risks of using expired eye drops include ineffective treatment of vision or other eye problems, eye inflammation and irritation, and in the worst case, infection. The specific effects depend on what the drops are intended to treat and how much time has passed since the printed expiration date. Most patients report few or no side effects from using eye drops that are past their start, but much of this depends on whether the eye drops have already been opened. Partially used bottles that have expired are generally more dangerous and carry more risks than those that are still sealed in their original packaging, although it should be noted that eye care practitioners never recommend using eye medication that has expired. .
Expired eye drops may be ineffective, but they can also cause eye irritation or infection.
There are two main types of eye drops: prescription and over-the-counter. Both versions will expire at some point, and their expiration dates are usually set, at least in part, according to how long the chemical suspension has been effective. Manufacturers typically print an expiration date on the bottle’s label or packaging that can be a year or more in the future, but in most cases the expiration date is around four weeks from the time they are opened. Exposure to oxygen can cause the droplets to become unstable and, over time, can lead to evaporation. The liquid may look the same in a few months, but it may actually contain different proportions of active and inactive ingredients than intended.
This risk is particularly serious for prescription products that are formulated to treat conditions such as glaucoma, chronic dry eyes, or allergies. Using old eye drops may not treat these conditions or may only partially treat them. Partial treatment can make illnesses last longer and sometimes get worse over time.
Irritation and inflammation can also occur with unstable or weakened eye drops. This is most common with prescription drops, but is also possible with even basic saline solutions, depending on the shelf life. Once the composition of the drug changes, it is no longer ideal for the surface of the eyeball. Higher levels of chemicals, salts, or other additives can cause redness and swelling.
Doctors generally advise against using expired eye drops.
The eyes are some of the wettest parts on the outside of the body and as such can be a breeding ground for bacteria. Patients are usually instructed to slowly squirt the drops into the eyeball, usually just below the eyelid. The dropper should never touch the surface of the eye or its fluids, but contact is still made in many cases. It can be very difficult to squeeze droplets into your own eye without accidentally touching the dropper to the surrounding fluid.
Even expired saline eye drops can irritate your eyes.
Once contact has been made, fluids can mix in the dropper and can even fall back into the main solution chamber. This usually doesn’t present a problem right away – which in most cases makes use of before the expiration date – but over time, the mixture can start to breed bacteria and contaminate the solution.
Reintroduction of a contaminated dropper into the sensitive area of the eye can result in serious consequences. Bacterial eye infections are often accompanied by swelling, inflammation, and itching. Medical attention is almost always needed as well, since the nature of most infections is to spread; If left untreated, things can penetrate deep into the eyeball, possibly affecting vision, or they can spread across the face.
The eyes are one of the wettest areas on the outside of the body.
Healthcare professionals often recommend that people get rid of expired eye drops and replace them with new products. It makes little sense to introduce the eyes to a liquid that is ineffective at best and contaminated at worst. Expired eye medications, especially those purchased over-the-counter, can usually be thrown in the household waste; these solutions are typically lightweight and likely to pose no risk to the environment or the health of others.
Depending on the contents of the medication, however, simply throwing away eye drops can be dangerous. Many pharmacies will accept expired medications for disposal, and most will at least advise patients about safe practices for getting rid of specific compounds.