A study done for the U.S. Army found that many drugs remain effective and usable even up to five years after their expiration date. Thus, some pharmaceutical experts do not believe all drugs should be automatically discarded immediately after they “expire.”
According to a report in HealthDay News, however, other experts think it is better to throw out all expired drugs rather than risk taking one that has become degraded or ineffective.
At the FDA science forum in 2002, the U.S. Army study was presented and revealed that 84% of the drugs examined (1,122 lots of 96 different drugs) remained stable up to 57 months after their listed expiration date.
Since these figures were found to vary widely from drug to drug, many pharmacists recommend that consumers take expiration dates seriously. The farther past the expiration date, the more unpredictable the effectiveness of the drug seems to be the message.
In fact, one study recently found that liquid antibiotics used to treat ear infections in children begin to lose their effectiveness after only two weeks even when refrigerated as required.
The Army study was also conducted under optimal circumstances where the drugs were kept in their original, unopened containers. Consumers simply do not do this since they usually take some of the medication before storing it away.
In addition to the obvious question of effectiveness, experts also point to other problems with taking “old” medicine. One is that the old drug may interact in an adverse way with new medications the patient may now be taking. The dosage could also vary for different diseases or illnesses.
Since you can never be absolutely certain that you are getting the maximum benefit from an expired drug, it is recommended that you go through your medications once a year and discard any medicine that has already expired.