Here's what happened when 8 long-expired medications with 15 different active ingredients were discovered in a retail pharmacy.
3 tablets or capsules from each batch, made up of 27 total samples for analysis, had all been stored there since before World War II! The oldest dated back to 1935 and some still contained their original labels which would indicate they expired more than 40 years ago - amazing right?!
This provided an opportunity to answer the question if medicines are still potent after expiry
There are tons of prescription drugs that hospitals and pharmacies throw away when they reach their expiration dates. These potentially valuable medications could have been used by people all over the world. It would appear that not all medicines can be stored for long periods of time. When medicines are indiscriminately thrown out when they reach the designated expiry date, scarce resources are lost with little gain in return because many patients will simply stop taking these expensive treatments when they reach the end date on their prescriptions.
The Experiment
Roy Gerona, a University of California, San Francisco, researcher who specializes in analyzing chemicals carried out the experiment and published it in October 2012 after presenting at the 2011 North American Congress of Clinical Toxicology in Washington, DC.
The science behind the experiment: doi:10.1001/archinternmed.2012.4501. The tablet was dissolved and sonicated in methanol, reconstituted with analysis buffer (10% methanol) before being analyzed via LC-MS/MS. The time-of flame ionization FP mass spectrometer saw use for negative polarity as well as positive; however, to better separate compounds by their charge they were separated using C18 polar column that had been eluting off at different rates due solely based on pH requirements. Data analysis was performed using Mass Hunter Qualitative and Quantitative Analysis and Quantification was performed by isotope dilution method with a 6-point calibration curve.
The Findings
12 of the 14 compounds were still as potent as they were when they were manufactured, some at almost 100% percent of labelled concentrations showing that active ingredients were still stable.
Disclaimer; This does not mean all expired drugs are safe. And this is not medical advice!
In fact, expiry dates are a big deal. For example, did you know - Tesco were fined £7.56m in 2021 for selling out of date food, and Morrisons have removed the expiry dates on Milk in an effort to reduce waste? Back to medicines and NHS explains why you should not take medicines after the expiry or use by date.
The Backlash
When Cantrell and Gerona published their findings in 2012, some readers accused them of being irresponsible. The authors weren't recommending the use of expired medication but rather reviewing an arbitrary system that dates are set by which can lead patients into confusion about when drugs should or shouldn’t be used- regardless if they have already passed their expiration date!
Let's do the math
Once a drug is launched, the makers run tests to ensure it continues being effective up until its labelled expiration date. Since they aren’t required to check beyond this point in most cases because regulations make extended testing expensive and time-consuming for manufacturers.
The US Department Health Resources Services Administration reports 1/3 (33%) of surveyed hospitals disposed 80% or more drug samples during FY2011; 90%(66) eliminated at least 97%.
We’re talking about an estimated $2 billion worth - just thrown away without any thought given as to whether there could still have been some value left inside.
Conclusion
The study shows that some prescription pharmaceuticals may retain their full potency for decades beyond the expiration date. This should be taken into consideration when considering current drug practices, which often only consider how long a medication has been stored at room temperature or below without being refrigerated after purchase but neglecting other factors.
This gives us more evidence to rethink current practices of drug expensing, which can be expensive and not as effective with some drugs like antibiotics - who would have guessed?!