Q: Should I really be concerned about the expiration date on medications?

A: You bet there's something to expiration dates. Yes, some prescription and over-the-counter products keep on working long after their expiration dates. The Food and Drug Administration (FDA), in fact, recently ordered pharmaceutical companies to test their products to determine how long they would still deliver as promised.

Counting on expiration dates to be bogus, however, can get you into trouble. There are well-known ways that certain products show their age. Aspirin begins to smell of vinegar as its active ingredient breaks down. Hydrogen peroxide no longer bubbles when you apply it to a wound. The sugar component of cough syrup crystallizes, a sign of that medicine's diminished effectiveness.

The above products do nothing for you beyond their expiration dates. If you're taking aspirin to thin blood, that's risk enough. But another product, tetracycline, can be poisonous if it's outdated or even poorly stored. (When you are correctly following the dosing instructions, no tetracycline or any other antibiotic will be left after the last day.) Another well-known medicine, nitroglycerin, also may do nothing after it expires, which can be fatal for heart patients.

There are few things worth knowing about drug expiration dates. First, the fact that pharmaceutical companies will soon be testing the longevity of their medicines and supplements does not mean that a given product will invariably last as long as stated. Products, after all, are tested under ideal conditions: storage within a specific temperature and humidity range, and away from light. Truth to tell, most medicine cabinets are too warm and humid for long-term storage of medicines. To make matters worse, a prescription drug begins its slow march to expiration once its original container is opened (at the pharmacy), not necessarily the day you buy it.

Here are a few tips to helping medicinal bygones be long-gones:

  • Make a good scan of your medicine cabinet and toss out all expired drug products.
  • Store medicines in their original containers, but without the cotton, which can promote fungal growth.
  • Whether or not they have expired, throw away all discolored medicines along with ointments showing marked separation. This also applies to any medicines you cannot identify.
  • If your doctor instructs you to take a prescription medicine "as needed," pay particular attention to expiration dates, but get the date from the manufacturer (say, two years from purchase), not from the pharmacist. In many states, pharmacies are permitted to write their own, earlier expiration dates on medicines.
  • When you do dispose of medicinal products, make sure they are out of reach of children and animals or take them back to your pharmacy to have them disposed of properly.

Should the milk in your refrigerator get too old, you'd pour it out, yet its curdled nature would do little more than give you a stomach ache. With medicines, over-the counter as well as prescription, you aren't just inviting indigestion. Depending on the medicine and its condition, you could also be playing Russian roulette with your health.