Paging Dr. Frischer - Medication expiration dates

Rummaging through my cupboards, I stumbled upon my favorite topical steroid cream and noticed that it had stamped on it an expiration date...from the 1990's! I kidded with my wife that this miracle cream only gets better with age, like a fine wine.However, we all know that medications do come with an expiration date. What does this date mean? Is that the date when we are to throw it away, or can we eek out another month, three months...or 15 years? Will that expired medication still be effective? Could it be dangerous? Americans spend 300 billion dollars each year on drugs, and disposing of them prematurely clearly costs a fortune. The expiration date indeed is significant, and the meaning depends on the type of drug, how it has been stored, and its chemical stability. Drug manufacturers were first required to put an expiration date on all products in 1979, in order to signify the date at which they would still guarantee the drug's full potency and safety. The average expiration date is between one and five years from manufacture. Much of what we know about how long medicines last comes from ongoing FDA studies conducted at the request of the military, beginning in 1986. With an expansive (and expensive) stockpile of drugs, the military faces the prospect of disposing and replacing everything periodically. The study originally showed that of over 3,000 lots of 122 drugs tested, 88% of those properly stored in their unopened containers remained stable for an average of five and a half years beyond the labeled expiration date. Many of these drugs, both prescription and over-the-counter, were perfectly safe and effective to use even 15 years beyond the expiration date! In general, liquid medicines tend to be less stable than solid forms. Any injectable medicine that has become cloudy or discolored should not be used. An EpiPen, for instance, loses its potency after its expiration date, as does insulin. Oral nitroglycerin, used for angina in heart disease, can lose its potency quickly once the bottle is opened. Replacement of nitroglycerin is recommended promptly, both because its effectiveness may be diminished and because its potency is so very critical. Vaccines are subject to quick degradation. Eye drops tend to not lose stability merely from age, but once they are opened, they are at high risk of getting contaminated due to the bottle repeatedly touching the eye and other skin. Common sense dictates that if a medication is powdery or crumbling, has a strong smell, or is an ointment or cream that has dried up, it should be discarded. Tetracycline, a commonly used antibiotic, can actually become toxic to the kidneys past its expiration date. Storing medication in a cool place, like a refrigerator, often helps it last longer. Conversely, storing it in heat or high humidity can shorten its life. The medicine cabinet in a steamy bathroom is far from the best location for medication storage, and leaving it in the car is likewise a poor idea. The best way to store medicine is in its original (and unopened) container. Some feel that the expiration date is a marketing ploy on the part of manufacturers to make us restock more frequently. Consider, however, that the dates are conservative in order to ensure that we are informed when they may be at less than full strength. Also note, for what it's worth, that expiration-date testing for longer periods could slow down the process of bringing new medicines to market, and the FDA does not require drug manufacturers to perform longer-term stability tests. What is my own bottom line: would I use an expired medicine, or would I throw it away? If this medicine were for the treatment of a chronic and potentially life-threatening disease like heart disease, seizures, serious allergic reactions, or other major conditions, then I would carefully abide by the expiration date and replace it on a regular and timely basis. If it is being used to treat a relatively minor problem such as headaches, allergies or mild pain, then taking a medication that is at less than its 100% effectiveness is not as critical. Always keep in mind that it will last longer if stored properly. Clearly, if you take one of these out-of-date medications, and it doesn't seem to work, discard and replace it. Always err on the side of safety! In my next column, I will discuss the proper ways to dispose of unwanted medication. Dr. Alan Frischer is former chief of staff and former chief of medicine at Downey Regional Medical Center. Write to him in care of this newspaper at 8301 E. Florence Ave., Suite 100, Downey, CA 90240.

********** Published: June 27, 2013 - Volume 12 - Issue 11