What is the expiration date/time after opening povidone-iodine?

Generally, the shelf life of povidone-iodine after opening may range from 7 to 30 days. However, its shelf life may be shortened if the povidone-iodine becomes contaminated. Detailed explanations are as follows:

If the povidone-iodine is in small bottles, it is more susceptible to external environmental factors during use, such as microorganisms and dust in the air, which may lead to a gradual decrease in its disinfecting effectiveness. Under normal circumstances, the shelf life of povidone-iodine in small bottles is usually around 7-10 days.

Large bottles of povidone-iodine are relatively more stable due to their larger capacity, so their shelf life after opening is longer, potentially extending to 10–30 days. To ensure the disinfecting effectiveness of large bottles of povidone-iodine, it is recommended to maintain their cleanliness and sterility during use and follow proper storage and handling methods.

If povidone-iodine becomes contaminated during use—for example, by bacteria or other microorganisms—it may become ineffective immediately. Therefore, when using povidone-iodine, it is important to take special care to avoid contamination—for instance, do not reinsert contaminated cotton balls or swabs into the bottle to dip into the solution, and do not pour unused povidone-iodine back into the original bottle. If contamination or abnormal conditions such as discoloration are observed, usage should be stopped immediately and replaced with new povidone-iodine.

Povidone-iodine should be stored in a cool, dry, well-ventilated place, away from direct sunlight and high temperatures. It is recommended to store it at temperatures below 20°C to minimize iodine volatilization and solution degradation.