Chances are you’ve got a few bottles of expired medicine lying around the house. So what happens when you’re in dire need of some cold medicine and the only package you’ve got is two years old? Here’s how expiration dates work.
Prescriptions and OTC drugs
In 1979, a law was passed that mandated that all drug manufacturers put a stamped expiration date on their drugs. This stamp represents the manufacturer’s guarantee of the full efficacy and safety of the drug. That doesn’t necessarily mean that the drug is not stable after this date; it simply guarantees that it is stable in a sealed container with full potency up to this date. The average expiration date is between one and five years.
A study conducted by the FDA found that 90 percent of more than 100 tested prescription and over-the-counter drugs were found to be safe and effective far past their expiration date—many up to 10 years. While the original effectiveness of the drug may decrease over time, many drugs can be considered safe for use past expiration (with the exception of certain drugs such as nitroglycerine, insulin, EpiPens and liquid antibiotics).
While the FDA does not require expiration dates for nutritional dietary supplements, manufacturers often include this information in an effort to ensure products provide consistent results. To set an expiration date, a manufacturer must perform stability tests to determine active ingredient degradation over time. And the FDA requires that manufacturers who put an expiration date on their products can prove that the product maintains the original potency listed on the label until the stamped expiration date.
Here is the general wisdom on the expiration dates of different types of supplements:
- Herbal, vitamin, mineral, enzyme and amino acid supplements slowly weaken with age. As a general rule of thumb, these supplements may maintain potency for 1-2 years following their expiration date.
- It is thought that quality B vitamins may not sustain potency following expiration, so it’s a good practice to purchase new B vitamins once yours are past the expiration date.
- Fish oils and probiotics can maintain potency for around three months past the posted expiration date.
- Juice or liquid and glandular supplements may maintain potency up to a year past the expiration date.
Generally, the higher the quality and grade of the supplement, the longer a dietary supplement will maintain potency past the expiration date. Natural supplements generally do not degrade into anything toxic or harmful over time—this also would be dependent on proper storage.
To ensure potency of any substance, make sure you store it safely. Always keep drugs and supplements in their original packaging. Keep them out of heat, moisture and light, and only refrigerate them if told to do so by your pharmacist. And never store your drugs in the bathroom cabinet, as the bathroom carries a lot of moisture.
Lastly, never flush prescription medications or supplements down the toilet. Wastewater treatment plants are not designed to remove and destroy drugs, and doing so can lead to contamination of drinking water as well as oceans, lakes and rivers. Polluting marine life in turn has a hazardous impact on our food chain and the drugs can end up back in our bodies. (Click here for more information about proper medication disposal.)
Kate Brainard attended Bastyr University’s doctorate program in Naturopathic Medicine. She currently manages Pharmaca’s La Jolla store