When you pick up besifloxacin, a prescription antibiotic eye drop used to treat bacterial eye infections. Also known as BESIVANCE, it's designed to kill bacteria on the surface of your eye. But like all medications, it doesn’t last forever. The besifloxacin shelf life matters because using expired drops can mean your infection doesn’t clear up—or worse, gets worse.
Most unopened besifloxacin eye drops last about 2 years from the date they were made, as long as they’re stored at room temperature away from heat and light. Once you open the bottle, the clock starts ticking faster. The FDA and manufacturers recommend using it within 28 days after opening. Why? Because even sterile solutions can get contaminated after the seal breaks. Bacteria from your fingers, air, or eyelashes can grow in the liquid, turning your medicine into a risk instead of a treatment. That’s why pharmacies often label the bottle with a discard date—don’t ignore it.
Storage plays a big role too. If you leave your besifloxacin in a hot car, on a sunny windowsill, or in a bathroom cabinet with steam from showers, the active ingredients can break down faster. You might not see a change in color or smell, but the drug could lose its strength. That’s not just wasteful—it’s dangerous. If your infection isn’t fully treated, resistant bacteria can survive and spread. And if you’re using it for a child or someone with a weak immune system, that risk multiplies.
Some people think they can extend the life of their medication by refrigerating it. For besifloxacin, that’s not recommended unless the label says so. Cold temperatures can change how the solution flows out of the dropper or cause particles to form. Stick to room temperature, keep the cap tight, and write the opening date on the bottle with a marker. That way, you’ll know exactly when to toss it.
You’ll also find posts here about how other antibiotics behave over time, how storage affects drug potency, and why some meds are safe to use past their printed date while others aren’t. We’ve got real-world examples from patients who’ve dealt with expired eye drops, what pharmacists actually see in their bins, and how to tell if your medicine has gone bad—even when it looks fine. Whether you’re managing a chronic eye condition or just got prescribed besifloxacin for a sudden infection, knowing how long it stays effective can save you from complications, extra visits, and unnecessary costs.
Learn how to properly store and use besifloxacin eye drops to ensure they remain effective. Avoid common mistakes that can reduce potency and risk treatment failure.
Continue Reading