The expiration dates on OTC medication packages are set by manufacturers. The product is guaranteed until the expiration date if it is stored in a suitable environment, Higgins says.
What manufacturers typically say about a product past the expiration date is that it has lost potency and is no longer as effective as before, she says.
Higgins says she wouldn't sell any medication past its expiration date. However, if someone is home sick with an OTC drug that expired Dec. 31, 2006, that drug might still do the job, she says. It is probably good for another month or so. People should be cautious about using drugs older than that.
Prescription drugs are another matter.
Some drugs, such as the antibiotic tetracycline, can become toxic, Higgins says. She recommends throwing prescription drugs out on their expiration date or at least checking with a pharmacist or doctor.
If the package's expiration date only lists a month and year, it's usually referring to the end of that month, Higgins says.
One problem with whether an expiration date is accurate is whether the consumer stores the medication properly, something many people don't do, Higgins says.
Medications should not be stored in the refrigerator unless the label states so, Higgins says. Refrigerators can have a dehydrating effect on medicines.
The bathroom and kitchen aren't good places because of humidity, which can shorten the expiration of the drug. Windowsills aren't good because the sunlight can affect the quality of medicine, even if it's bottled.
Most medications should be kept at room temperature, such as in a hall closet on a high shelf out of children's reach, Higgins says.
What's that mean?
Some foods such as dairy and frozen products tend to have dates stamped on them with various phrases that typically have nothing to do with the safety of the product, says Ryan Seavolt, Food Program supervisor in Washington County Health Department's Environmental Health Division.
According to the Food and Drug Administration's Web site, the phrases and their meanings are:
"Sell by": tells the retailer how long to display a product. The designation guides the rotation of shelf stock and allows time for a product to be stored and used at home. The date is not a food safety concern but is quality-driven.
"Best if used by": The phrase with a date represents the recommended time limit within which the food should be used for best flavor or quality. This does not designate a purchase or safety date.
"Use by": This designates the last date a consumer is recommended to use a product while it is at peak quality; recommended for best flavor or quality; is not a sell-by or food safety date.
Expiration date: indicates the last day a food should be eaten or used. The FDA says foods bought or used after the expiration date could contain bacteria and might not be safe to eat.
When a "use by" date has passed on a cold food item, the food might still be safe to eat if it was kept at the appropriate temperature, Seavolt says.
When inspecting facilities where food preparation and service take place, such as grocery stores and restaurants, Seavolt is checking to make sure refrigerated items are kept at 45 degrees or lower and frozen foods are kept at 0 degrees or lower. These are state-regulated temperatures, whereas the federal government goes by 40 degrees or colder for refrigerated items.
The low temperature is to inhibit the growth of bacteria.
"I think if you went into a lot of residential places, you'd probably find a little higher than (45 degrees)," Seavolt says.
In addition to monitoring the temperature of their refrigerator and freezer, Seavolt says people shouldn't keep their freezers fully packed. That could restrict air flow and make products warmer.
The codes on canned goods are for purposes of tracing back food in case there is an outbreak or illness, Seavolt says.
If the can is dented along the top, bottom or vertical seam, don't buy it or eat the food. Even though the can might not be visibly leaking, bacteria might have entered the can and could be growing inside if it's severely dented. One of the more common bacteria that can multiply in canned goods is clostridium botulinum, Seavolt says. That is the bacterium that produces the toxin causing botulism.