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Drug Expiration Dates
By Laurie P. Cohen Do drugs really stop
working after the date stamped on the bottle? Fifteen
years ago, the U.S. military decided to find out. Sitting
on a $1 billion stockpile of drugs and facing the
daunting process of destroying and replacing its supply
every two to three years, the military began a testing
program to see if it could extend the life of its
inventory.
The testing, conducted by the U.S. Food and Drug
Administration, ultimately covered more than 100 drugs,
prescription and over the counter. The results, never
before reported, show that about 90% of them were safe
and effective far past their original expiration date, at
least one for 15 years past it.
In light of these results, a former director of the
testing program, Francis Flaherty, says he has concluded
that expiration dates put on by manufacturers typically
have no bearing on whether a drug is usable for longer.
Mr. Flaherty notes that a drug maker is required to prove
only that a drug is still good on whatever expiration
date the company chooses to set. The expiration date
doesn't mean, or even suggest, that the drug will stop
being effective after that, nor that it will become
harmful.
MARKETING ISSUE
"Manufacturers put expiration dates on for marketing,
rather than scientific, reasons," says Mr. Flaherty, a
pharmacist at the FDA until his retirement last year.
"It's not profitable for them to have products on a shelf
for 10 years. They want turnover."
The FDA cautions that there isn't enough evidence from
the program, which is weighted toward drugs needed during
combat and which tests only individual manufacturing
batches, to conclude that most drugs in people's medicine
cabinets are potent beyond the expiration date. Still,
Joel Davis, a former FDA expiration-date compliance
chief, says that with a handful of exceptions - notably
nitroglycerin, insulin and some liquid antibiotics - most
drugs are probably as durable as those the agency has
tested for the military. "Most drugs degrade very
slowly," he says. "In all likelihood, you can take a
product you have at home and keep it for many years,
especially if it's in the refrigerator."
MANUFACTURERS' VIEW
Drug-industry officials don't dispute the results of the
FDA's testing, within what is called the Shelf Life
Extension Program. And they acknowledge that expiration
dates have a commercial dimension. But they say
relatively short shelf lives make sense from a
public-safety standpoint, as well.
New, more-beneficial drugs can be brought on the market
more easily if the old ones are discarded within a couple
of years, they say. Label redesigns work better when
consumers don't have earlier versions on hand to create
confusion. From the companies' perspective, any liability
or safety risk is diminished by limiting the period
during which a consumer might misuse or improperly store
a drug.
"Two to three years is a very comfortable point of
commercial convenience," says Mark van Arandonk, senior
director for pharmaceutical development at Pharmacia &
Upjohn Inc. "It gives us enough time to put the inventory
in warehouses, ship it and ensure it will stay on shelves
long enough to get used."
But companies uniformly deny any effort to spur sales
through planned obsolescence.
WHY NOT LONGER?
Now that the FDA has found that many drugs are still good
long after they have supposedly expired, why doesn't it
advocate later expiration dates for consumer drugs? One
reason is that the consumer market lacks the military's
logistical reasons to keep drugs around longer.
Frank Holcombe, rectumociate director of the FDA's office
of generic drugs, says that in many cases a manufacturer
could extend expiration periods again and again, but to
support those extensions, it would have to keep doing
stability studies, and keep more in storage than it would
like.
Mr. Davis adds: "It's not the job of the FDA to be
concerned about a consumer's economic interest." It would
be up to Congress to impose changes, he says. As things
stand now, expiration dates get a lot of emphasis. For
instance, there is a campaign, co-sponsored by some drug
retailers, that urges people to discard pills when they
reach the date on the label.
And that date often is even earlier than the one the
maker set. That's because when pharmacists dispense a
drug in any container other than what it came to them in,
they routinely cut the expiration date to just one year
after dispensing. Some states even require pharmacists to
do this.
Meanwhile, poor countries - under urging from the World
Health Organization - often reject drug-company donations
of much-needed medicines if they are within a year of
their expiration dates.
It isn't known how much of the $120 billion-plus spent
annually in the U.S. on prescription and over-the-counter
medicines goes to replace expired ones. But in a poll
done for The Wall Street Journal by NPD Group Inc. of
Port Washington, N.Y., 70% of 1,000 respondents said they
probably wouldn't take a prescription drug after its
expiration date; 72% said the same of an over-the-counter
remedy.
"People think that, upon expiration, drugs suddenly turn
toxic or lose all their potency," says Philip Alper,
professor of medicine at University of California at San
Francisco. In his own practice, Dr. Alper says, "I
frequently hear from patients who can't afford medicine -
that they have thrown away expired drugs."
He says companies should be required to test drugs for
longer periods and set later expiration dates when
results warrant.
Some manufacturers first began putting expiration dates
on drugs in the 1960s, although they didn't have to. When
the FDA began requiring such dating in 1979, the main
effect was to set uniform testing and reporting
guidelines. As now required by the FDA, so-called
stability testing analyzes the capacity of a drug to
maintain its identity, strength, quality and purity for
whatever period the manufacturer picks. If the company
picks a two-year expiration date, it needn't test beyond
that.
Testing for a two-year expiration doesn't initially
entail holding a drug for two years. Rather, the drug is
tested by subjecting it to extreme heat and humidity for
several months, then chemically analyzing each
ingredient's identity and strength. (After the date is
set and the drug is marketed, testing continues for the
full two years.) The FDA also uses chemical analysis in
testing for possible shelf-life extension; it doesn't
test on human subjects. Testing conditions are such that
any medicine that meets, say, the standards for a
two-year expiration date probably lasts longer, the FDA
and drug companies agree.
STILL GOOD
Consider aspirin. Bayer AG puts two-year or three-year
dates on aspirin and says that it should be discarded
after that. Chris Allen, a vice president at the Bayer
unit that makes aspirin, says the dating is "pretty
conservative"; when Bayer has tested four-year-old
aspirin, it remained 100% effective, he says.
So why doesn't Bayer set a four-year expiration date?
Because the company often changes packaging, and it
undertakes "continuous improvement programs," Mr. Allen
says. Each change triggers a need for more
expiration-date testing, he says, and testing each time
for a four-year life would be impractical.
Bayer has never tested aspirin beyond four years, Mr.
Allen says. But Jens Carstensen has. Dr. Carstensen,
professor emeritus at the University of Wisconsin's
pharmacy school, who wrote what is considered the main
text on drug stability, says, "I did a study of different
aspirins, and after five years, Bayer was still
excellent. Aspirin, if made correctly, is very stable."
Only one report known to the medical community linked an
old drug to human toxicity. A 1963 Journal of the
American Medical rectumociation article said degraded
tetracycline caused kidney damage. Even this study,
though, has been challenged by other scientists. Mr.
Flaherty says the Shelf Life program encountered no
toxicity with tetracycline and typically found batches
effective for more than two years beyond their expiration
dates.
PLEA FROM THE AIR FORCE
The program dates to a U.S. effort begun in 1981 to
increase military readiness by buying large quantities of
drugs and medical devices for the armed forces. Four
years later, more than $1 billion of supplies had been
stockpiled. The General Accounting Office audited Air
Force troop hospitals in Europe and found many supplies
at or near expiration. It warned that by the 1990s, more
than $100 million would have to be spent yearly on
replacements.
The Air Force Surgeon General's office asked the FDA if
it could possibly extend the shelf life of these drugs.
The FDA had the equipment for stability testing. And
because it had approved the drugs' sale in the first
place, it also had manufacturers' data on the testing
protocols. Testing for the Air Force began in late 1985.
In the first year, 58 medicines from 137 different
manufacturing lots were shipped to the FDA from overseas
storage, among them penicillin, lidocaine and Lactated
Ringers, an intravenous solution for dehydration. After
testing, the FDA extended more than 80% of the expired
lots, by an average of 33 months.
In 1992, according to the FDA, more than half of the
expired drugs that had been retested in 1985 were still
fine. Even now, at least one still is. Such results came
as a revelation for Army Col. George Crawford when he
took over military 0versight of the program in 1997. He
is a pharmacist, but "nobody tells you in pharmacy school
that shelf life is about marketing, turnover and
profits," he says. (The drug makers don't agree that it
is, however.)
HOW IT WORKS
The military's base for the program is a dingy barracks
room in Fort Detrick, Md. There, a group headed by Air
Force Lt. Col. Greg Russie, who recently took over from
Col. Crawford, tracks drugs that are near expiration at
defense facilities all over the world, selecting many for
retesting. They are shipped to the FDA, which sends them
to its laboratories.
The FDA's lab in Philadelphia recently tested five
automatic injectors containing an antidote to chemical
poisoning, which were purposely held for three months in
conditions even hotter and more humid than the FDA
requires in consumer testing of drugs. The FDA tested the
drug contained in the injectors, pralidoxime chloride, by
separating its ingredients and measuring the strength and
quality of each, then applying a computer model to
determine whether a shelf-life extension was warranted.
The injectors' original expiration date was November
1985. The FDA had retested them periodically ever since,
each time approving their continued use. The batch, made
by Ayerst Laboratories, now part of American Home
Products Corp.'s Wyeth-Ayerst unit, is 18 years old. It
is 15 years beyond the expiration date applied by Ayerst.
The FDA found it is still good.
A spokesman for Wyeth-Ayerst says it "uses scientific
data to establish expiration dates" and "tries to have
the longest possible dating on products that scientific
data supports." The company is aware of the FDA
retesting program. It says it can't comment specifically
on the injectors tested by the FDA.
A FEW FAIL
Shelf-life extensions are "intentionally conservative,"
the FDA's Mr. Flaherty told military brass in a 1992
speech. He says that if the agency extended an expiration
date by 36 months, it had concluded the lot would retain
all of its safety and efficacy for at least 72 months. A
very few drugs aren't retested. The military has found
that water-purification tablets and mefloquine
hydrochloride, for malaria, routinely fail stability
testing beyond their expiration dates, so it has removed
them from the program.
Also excluded are large-volume intravenous solutions,
such as saline. "We don't like to test those," says Col.
Crawford. "Not because we can't, but because it would be
politically sensitive if G.I. Joe was lying in bed and
saw it had originally expired three years ago."
Mr. Flaherty has said that while he tested a handful of
drug batches that didn't even make it to their expiration
dates, most drugs were "surprisingly durable." In one
instance, he says, drugs labeled for room-temperature
storage had been kept for two years in a warehouse in
Oman that averaged 135 degrees Fahrenheit in the daytime.
Upon expiration, the drugs, which included the local
anesthetic lidocaine and atropine, a nerve-gas antidote
also used by eye doctors to dilate pupils, "were well
within the standards for potency and other quality
characteristics," he says.
STABLE MOLECULE
One medicine the FDA has endorsed for extensions is
ciprofloxacin hydrochloride tablets, an antibiotic
marketed by Bayer as Cipro. One batch had an expiration
date of March 1989. More than 9 1/2 years later, the FDA
found the tablets still good; it then extended some of
them for 18 more months and others for 24 more months.
Albert Poirier, quality-assurance director for Bayer's
pharmaceutical division, says he isn't surprised because
Cipro "is a stable drug molecule" in tablet form. "We go
for a shelf life that will be safest for patients," he
says. "We want the drug to be used up within three years.
We wouldn't want a patient to have it for 10 years
because they'd have an old package insert" that might
omit new information or contra-indications and because
"we'd have no control over how they'd store the drug
during this time."
Another extended drug is Thorazine, a tranquilizer
chemically known as chlorpromazine tablets. Batches
bearing December 1996 expiration dates - unused and
unopened, as is the case with all drugs evaluated in the
Shelf Life program - were tested in July 1998 and
extended for two years. A spokesman for the maker,
SmithKline Beecham PLC, says it applies an expiration
date 24 months after manufacture. "We think that is the
appropriate expiration date," he says. "We don't benefit
from short expiration dates."
Some other drugs the FDA has extended at least two years
beyond their expiration dates are diazepam, sold as
Valium; cimetidine, sold as Tagamet; phenytoin, sold as
Dilantin; and the antibiotics tetracycline and
penicillin.
BIG SAVINGS
On a cost-benefit basis, the program's returns have been
huge. The first year, the Air Force paid the FDA $78,000
for testing and saved 59 times that sum by not needing to
replace the drugs. After other services joined, the
military from 1993 through 1998 spent about $3.9 million
on testing and saved $263.4 million on drug expense,
according to Lt. Col. Russie.
Says Mr. Flaherty: "We've cost the pharmaceutical
companies hundreds of millions of dollars in sales of new
stuff to the Department of Defense." More than 12 years
ago, Messrs. Flaherty and Davis explained the program to
drug-company chemists at a meeting of the American
rectumociation of Pharmaceutical Scientists in
Woodbridge, N.J., going into detail about how the FDA
decided whether to extend a given expiration date. Mr.
Davis concluded by noting how much the U.S. had saved by
extending shelf lives instead of "destroying large
quantities of still-useful medical products... ."
Mr. Flaherty says the FDA was keenly aware that if its
methodology was flawed, or its results incorrect even
once, its credibility would be attacked. Yet FDA
officials say that during the program's 15 years, drug
makers have never objected to any of its procedures or
findings. "They may not have liked what we were doing,
but they weren't able to challenge it," he says.
THE MESSAGE TO CIVILIANS
While the military is finding it can keep most drugs
longer, civilians hear quite a different message. For
instance, a campaign called the National Expired and
Unused Medication Drive has collected and destroyed 36
tons of drugs since 1991, says its founder, Kathilee
Champlin. Ms. Champlin, of Colorado Springs, Colo., says
her interest derives from experience working with the
elderly and seeing how hard it was for them to keep track
of all their medications. She says she wasn't aware of
any FDA program to extend drugs' shelf lives.
Her group has gained sponsorship from the some big drug
retailers, including Wal-Mart Stores Inc. It sponsors the
campaign to be "a good corporate citizen," says Frank
Seagrave, vice president of pharmacy merchandising. "We
believe that people should dispose of unused prescription
medicines a year after they get
them," he says, adding that Wal-Mart sometimes gives
people a free bottle of vitamins if they bring in expired
drugs.
Many pharmacists also play a role in shelf lives. The
U.S. Pharmacopeia, a not-for-profit scientific group that
develops standards for the drug industry, urged in 1985
that pharmacists set expiration dates at no more than one
year if they were dispensing drugs in a bottle other than
the manufacturer's original packaging. "New containers
may let in more moisture and heat than the container the
manufacturer used for the stability study," accelerating
the drug's degradation, says the USP General Counsel
Joseph Valentino.
The recommendation became a USP requirement in 1997. As a
result, "the majority of pharmacists shorten the
manufacturers' expiration dates" on prescription drugs to
one year or less, says Susan Winckler, an official of the
American Pharmaceutical rectumociation. In fact, in 17
states, pharmacists now are legally required to do so.
Ms. Winckler says shortening the dates makes sense
because many people store drugs in moist bathrooms. She
says the one-year rule is "motivated by product integrity
and not by profit." Original at: THE WALL
STREET JOURNAL March 29, 2000
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