Some 'expired' medicine OK, tests say.

Byline: Michael Woods

Jun. 6--With a migraine headache threatening, reach for Imitrex, the prescription drug that brings these debilitating headaches to a screeching halt. The pharmacy label warns: "Discard after February 2005." Those tiny tablets cost $16 each, almost their weight in gold.

Can you still take it in June?

Ask the same questions for scores of other prescription drugs, which cost people in the United States more than $160 billion annually.

The expiration dates on jugs of milk and cartons of yogurt tell consumers when a product goes bad. That may not always be true with prescription drug labels, according to research.

Government tests have found that some drugs stay fresh for years longer, enabling the military to save millions of dollars in replacing "expired" drugs.

While the American Medical Association has urged the pharmaceutical industry to see if consumers are wasting money by discarding drugs that are still safe and effective, nothing has been done.

The research raises questions about how seriously consumers should take expiration dates on some medicines, but leaves them without key information to make decisions, said Stephen R. Byrn. He is an expert on drug stability at Purdue University.

"A consumer really needs to know what they are doing to take a drug…