Expiration dates on antibiotic pills, capsules and caplets are, essentially, a scam.
All you have to do is Google "expiration dates antibiotics" and the first citation given is from a Harvard heath letter entitled "Drug Expiration Dates - Do They Mean Anything?"
That post summarizes a 20-year study done by the FDA for the U.S. military:
"It turns out that the expiration date on a drug does stand for something, but probably not what you think it does. Since a law was passed in 1979, drug manufacturers are required to stamp an expiration date on their products. This is the date at which the manufacturer can still guarantee the full potency and safety of the drug.
"Most of what is known about drug expiration dates comes from a study conducted by the Food and Drug Administration at the request of the military. With a large and expensive stockpile of drugs, the military faced tossing out and replacing its drugs every few years. What they found from the study is 90% of more than 100 drugs, both prescription and over-the-counter, were perfectly good to use even 15 years after the expiration date.... So the expiration date doesn't really indicate a point at which the medication is no longer effective or has become unsafe to use.... Is the expiration date a marketing ploy by drug manufacturers, to keep you restocking your medicine cabinet and their pockets regularly? You can look at it that way."
The Wall Street Journal put this story on their front page a few years back.
But don't take my word for it: You can read the article, in its entirety, right here.
"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."
How can your doctor or vet not know this?
Well, to start with, on some important issues, veterinarians are often taught very little. The entire "course" given on canine nutrition, for example, may be a single lecture from a dog food salesman. The lecture on flea and tick remedies may be a lecture from a Merial salesperson who will detail "the spread" to be made from selling non-prescription Frontline as if it were a prescription drug (hint: it's not).
As for antibiotics, vets will learn by heart the branded and generic names of variouus drugs, and what they treat, but they may not learn other essential information.
And, as alarming as it may sound, that's true for many human doctors too.
Pharmacist and U.S. Army Colonel George Crawford, who used to be in charge of the Department of Defense's pharmaceutical Shelf Life Extension Program (SLEP) notes :
"Nobody tells you in pharmacy school that shelf life is about marketing, turnover and profits."
You might think veterinarians and doctors would learn about this stuff in a Continuing Medical Education (CME) course, right?
Except there is a little joker in the deck.
You see, those CME courses are heavily subsidized by drug and vaccine makers, who help pay the speaker fees and travel costs for many of the lecturers.
Drug and vaccine makers make money when people throw good medicine down the drain, and they make money when dogs are over-vaccinated.
The business of canine health care is business, and good health and integrity often take the hind post.
Everyone in the system -- vets, pharmacies, and manufacturers -- profit when dogs are over-vaccinated and non-expired medicines are thrown down the drain.
Billions of dollars are wasted every year as a consequence. But do you have to be part of that?
No, you do not.