Many of us keep unused medicines in our homes, whether left over from a prescription or purchased over-the-counter for some future need. All medicines will eventually expire –what do you do then?
First let’s step back and take a look at what expiration dates mean.
For over-the-counter medicines, you’ll find an expiration date printed on the packaging by the manufacturer. This date refers to the time beyond which the manufacturer says the medicine should no longer be used. This date assumes proper storage, which may not hold true if a medicine is exposed to extreme heat, cold, moisture or too much light, or is stored at room temperature if it is supposed to be refrigerated. If an expiration date is printed as only a month and year (e.g., 08/19), that means it expires on the last day of the indicated month.
For medicines filled in a pharmacy, an expiration date (actually more appropriately called a “beyond-use” date) is provided on the pharmacy label. Generally, this date is 1 year after the prescription is dispensed, but the actual medicine may have come from a stock bottle with a manufacturer’s expiration date further into the future. This 1-year expiration date printed on the label indicates that the pharmacy can only vouch for the medicine’s “freshness” for 12 months from when it left the pharmacy. Some medicines have much shorter “beyond-use” dates, such as an antibiotic suspension that is dated for 14 days after dispensing.
So do the dates really matter? An expiration date stands for the last day on which the drug is guaranteed to be safe and effective if stored properly. But in reality, medicines are often still safe for many years beyond these dates. Theoretically, medicines could become dangerous over time – breaking down into another substance in normal storage conditions; however, tetracycline is the only drug known to cause harm over time, and only very rarely and with older manufacturing processes no longer in use.
More important to note is the idea of loss of effectiveness, or potency. The potency of most medicines declines gradually. A drop in potency for some medicines can be concerning – such as for medicines that require a very specific dosage to work properly or that require refrigeration or protection from light – although for most medicines a small reduction in potency will not be important. The problem is that we usually do not know how many months or years it takes for potency to be “too low.” A lower potency acetaminophen tablet taken for a headache may simply mean less effective pain relief; a lower potency antibiotic can fail to treat an infection; a lower potency birth control pill may mean a pregnancy!
We recommend the following when it comes to a medicine’s expiration date: