The question is common and it seems so simple. Do we need to worry about medicines going bad if they are used beyond their expiration date?
The answer is a bit more complicated than you might think. We recently received the following question from a reader of this column: “When I picked up a prescription from the pharmacy, the pharmacy label had a ‘use before’ date of 09/04/10. The manufacturer’s label, under the pharmacy label, had an ‘expiration’ date of Dec 2012. Why is this?”
We pointed out that the one-year “use by” date is legally required in many states. It is also convenient, since computers can easily generate a date one year from the dispensing day when printing the label. This date rarely coincides with the manufacturer’s actual expiration date.
Our answer generated controversy, especially among pharmacists. Several were offended by the suggestion that convenience would play any role. A few pointed out that the one-year discard date is mandated by state law.
One gentleman objected to any idea of paying attention to the manufacturer’s expiration date: “I have been a pharmacist in New Jersey for 50 years, and I think your explanation is off-base. The manufacturer’s expiration date assumes that the drug remains sealed in the original bottle under carefully controlled conditions.
“Once the patient opens the bottle and stores it in a bathroom or kitchen, those conditions don’t apply. The heat and humidity will cause rapid deterioration. People may assume that it is all right to use a drug up to the manufacturer’s expiration date, and that would be a mistake!”
Drug companies do test their drugs for stability under controlled conditions. Most drugs have an established shelf life of one to five years, but research shows that they often last much longer.
Extreme conditions can lead to problems, though this is not always due to improper storage by the patient. Mail order prescriptions are frequently exposed to extreme temperatures even before the patient receives them. When pills sit in a mailbox for hours they may bake or freeze depending on the time of year.
Many people worry that medication past its expiration date will morph into something dangerous that could be harmful. Fortunately, a new review from The Medical Letter on Drugs and Therapeutics (December 14/28, 2009) lays that fear to rest. There are no reports of harm from taking a medicine that has exceeded its expiration date. In many cases, drugs retain their potency for up to five years after the manufacturer’s expiration date.
One important exception is injectable epinephrine found in EpiPen. This medicine is used to reverse a life-threatening allergic reaction. Patients are taught how to give themselves injections in an emergency. Once it is past its expiration date, it may not be potent enough to do its life-saving job. Consequently, EpiPens should be replaced regularly.
Liquid medicine should never be allowed to freeze and medicine should be stored away from heat and humidity. That means not in bathroom medicine cabinets.
If you want to know the manufacturer’s expiration date for your medicine, ask the pharmacist to put it on the label when you hand in your prescription.

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  1. hr
    Reply

    How about for athlete’s foot — micatin, or clotrimazole — expiration date problems? The kid started complaining ten minutes after the pharmacy closed, and the crimp date is on the clotrimazole is 2009 (I’m guessing it’s still good). The Micatin, um, that’s 1995 spray can version. Maybe not.

  2. Asthmatic
    Reply

    Thanks for the information here. I just used a nebulizor with albuterol sulfate inhalation solution that expired 14 months ago. The vials were kept in a cool dry location, in the original, sealed foil containers, inside a sealed box. My copay was $104 in 2009 and I’m sure it costs more now. I haven’t needed it for a very long time. If the only potential danger is lack of potency I feel comfortable using any kept sealed in the foil for up to 60 months past the expiration date as long as I have a hand held rescue inhaler for backup.

  3. joanne
    Reply

    I also have used “old” tylenol or ibuprofen. However, there is one drug I can think of that you SHOULD NOT use after it’s expiration date and that would be tetracyclines. Unfortunately people quit taking their antibiotics once they feel better and save the balance for another time. Tetracycline, however produces something called the Fanconi syndrome, whereas the outdated medicine can cause kidney damage. Be careful!

  4. Greg Pharmacy Student
    Reply

    RMH and R,
    Please don’t use 2 Epi-Pens. It is important to know why there are expiration dates. As medications are exposed to varying temperatures, humidities and to light the medication degrades, just like if you were to compare a newly painted house with one painted 10 years ago. If your medications is exposed to more of the elements it degrades faster. There is no good way to determine the potency of your medication.
    In the specific instance of your Epi-Pen most pens will direct you to seek medical attention after use and only use a second dose when symptoms return and you are not able to seek medical attention.
    R – if your medication is sealed in its original bottle it sounds like it would still be good if it was still in date. Always consider the risks and benefits of your options in most cases spending the money on “in date” medication makes much more sense than taking possibly harmful drugs.

  5. C.A.S.
    Reply

    You should consider this if you have a condition that can get out of control quickly such as very high blood pressure, diabetes and extreme pain. In the event of a NATIONAL EMERGENCY, you may not be able to get your medications for a month, or even longer. I, for one, am going to keep several months worth of such medications that I have saved up. The expiration date will mean nothing in this case.

  6. rmh
    Reply

    Am allergic to wasp/hornet stings; so carry epi-pens in both vehicles, shaving kit, house and shop. They are quite expensive, so do not replace annually; was very unhappy to read that the contents have a very limited shelf life–most of my epi-pens are well over a year old; two were replaced last spring when had a couple of stings, injected epi-pen, drove to EMT place and waited to see if reaction. When none in an hour, went home and about my business. If potency is reduced after a year, then should I use two of the older pens if stung again?

  7. William H Fleming, MD
    Reply

    I am a retired physician. Many years ago, I read a report about physicians family members having an unusually high incidence of nephritis. When investigated, they found the reason was that physicians often used old (expired) samples of medicines from their office to treat their own family. The major culprit for the problem was expired antibiotics. So, there IS a real serious risk when taking some expired medications.

  8. R
    Reply

    I understand how kitchen-stored medications may be near a heat-source (stove, toaster, coffee maker) but how much would an entric-coated capsule inside a sealed bottle inside a closed bathroom cabinet be affected by humidity? Is there research into same?

  9. Robert
    Reply

    I’ve always assumed that medicine isn’t as effective after it has expired, but I wouldn’t be worried about using it beyond that date.

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