Polymyxin eye drops are a common medication prescribed to treat bacterial eye infections, such as conjunctivitis or blepharoconjunctivitis. These drops contain antibiotics, like polymyxin B and trimethoprim, which work by killing the bacteria responsible for the infection. Proper and safe use of any medication, especially for eye health, is important.
Understanding Expiration Dates
Polymyxin eye drops, like all medications, have expiration dates that indicate when their safety and effectiveness can no longer be guaranteed. A printed expiration date is found on the packaging or bottle, applying to an unopened product stored correctly. This date is set based on stability testing by the manufacturer.
A separate, shorter “open-bottle expiration” period applies once the sterile seal is broken. Opening the bottle introduces a risk of contamination from bacteria, viruses, and fungi, despite the presence of preservatives in many multi-dose eye drops. General guidelines recommend discarding eye drops one month after opening, even if the printed expiration date is further in the future. Some products may be used until the printed expiration date even after opening, so check the specific product’s instructions.
Risks of Using Expired Drops
Using polymyxin eye drops past their expiration date or beyond their recommended open-bottle period carries several potential risks. The primary concern is reduced medication effectiveness. Active ingredients can degrade over time due to exposure to air and light, meaning the drops may not properly treat the infection, potentially worsening the condition or prolonging discomfort.
Expired eye drops also pose a risk of contamination. Once opened, the bottle’s sterile environment is compromised, and bacteria or fungi can grow, especially as preservatives may break down over time. Applying contaminated drops can introduce harmful microorganisms, leading to new or more severe eye infections. Using expired drops can also cause eye irritation, redness, stinging, or other adverse reactions due to chemical changes.
Safe Handling and Disposal
Proper handling and storage are important for polymyxin eye drops. Always store the drops according to package directions, at room temperature and away from direct sunlight. Avoid touching the dropper tip to your eye, eyelid, or any other surface to prevent contamination. Never share your eye drops with anyone else, as this can spread infection.
When polymyxin eye drops expire or are no longer needed, proper disposal is necessary to prevent harm and environmental contamination. The best method is to utilize local drug take-back programs, often available at pharmacies or healthcare facilities. If a take-back program is not accessible, mix the drops with an undesirable substance like coffee grounds or cat litter, seal the mixture in a leak-proof bag or container, and dispose of it in household trash. Avoid flushing eye drops down the toilet or pouring them down the sink, as this can contaminate water sources.