We wrote before about shelf life issues in general, and pointed out that the expiry dates on most medicines are ridiculously conservative, and that it is common for medicines to retain full potency for many years subsequent to their printed expiry date – assuming they have been stored in optimum conditions.
Here’s an interesting article that cites two studies of the extended effectiveness of medicines beyond their stated expiry dates.
The larger study was conducted by the DoD and FDA, and tested 3,005 different drugs. Of these, 88% maintained their full potency for an average of 5 and a half years after their official expiration dates.
The other study was by the University of California, San Francisco, which looked at eight different medicines which contained, between them, 15 different active ingredients. The samples were between 28 and 40 years old, and in their testing, the researchers determined that 12 of the 14 ingredients tested still retained at least 90% of their potency (the two exceptions being aspirin and amphetamines).
Conventional wisdom says you should throw away old medicines that have passed their expiry dates. We disagree. Apart from the specific exceptions of insulin, liquid suspension antibiotics and nitroglycerin (all of which do have short shelf lives), you can – and should – safely keep and use almost all other medicines for at least 10 years past their expiry dates.
Although the UCSF study showed that aspirin and amphetamines slowly lost their full effectiveness over extended time, they still remained partially effective and if your aspirin isn’t working as well as it formerly did, that is hardly life threatening and easily remedied by simply taking more aspirin.
We would recommend, with prescription medications, that you get new prescriptions as appropriate, but stockpile unused portions of prescriptions and use the older medicine first, rotating it the same as you would food. Pay attention to the recommended storage conditions for each medicine – some are best kept at room temperature, others in cooler environments, and all of course should be in a dark area away from sunlight.
The traditional bathroom cabinet is often not the best place to store medicines, due to it having substantial variations of temperature and humidity.
Note that you should always take all of any course of antibiotics. Never stop part way through just because you seem to be feeling better. So it will be more difficult to stockpile antibiotics, although we’ve found many physicians are understanding and willing to prescribe extra antibiotics – particularly if you explain the need as perhaps a desire to have some emergency antibiotics prior to traveling to a foreign country.
Note also – we are neither doctors nor pharmacists. If you are being treated for a serious life-threatening illness, you should be careful before taking potentially less effective very old medicine. If in doubt, don’t risk your health now in favor of creating a supply of medications for some possible future need.