Understanding Expiration Dates and Keeping Your Blood Sugar Readings Accurate

Making informed decisions about your diabetes management is crucial. This article explores the importance of using unexpired diabetic test strips for accurate blood sugar readings.

There are more than 37 million Americans currently living with diabetes, and a whole lot of us rely on a blood glucose meter to measure our blood sugar each day.

While there’s little debate about the effectiveness or accuracy of today’s blood glucose meters from leading brands like Contour Next, FreeStyle, Accu-Chek, and OneTouch, there still seems to be some confusion about diabetic test strips.

Basically, what’s up with the expiration dates? Are they real? Can you use test strips beyond the expiration date? Are they like yogurt or milk expiration dates, which most of us would have to admit to ignoring – at least for a few days beyond that expiration date – on occasion?

Why Do Diabetic Test Strips Expire?

Diabetic test strips most certainly do expire, and here’s why. What makes diabetic test strips work are organic enzymes and other chemicals. In other words, it’s not technology that drives your blood sugar reading; it’s enzymes and other sensitive stuff placed on the strip's tip. Your blood reacts with these elements, and the reaction is then transferred into an electrical current that your meter reads to provide you with an accurate blood glucose measurement.

But remember, this accuracy depends on the enzymes' viability at the test strip's end. These enzymes are natural elements, and they will assuredly degrade over time. Once they do, the accuracy of your blood sugar reading will more than likely be compromised.

In a recent article posted on, diabetes author and educator Wil Dubois describes test strips quite nicely. He says, “A test strip is more animal and vegetable than a machine, and any test strip that’s old enough will eventually give you bad information.”

It’s clear that diabetic test strips will eventually expire. But is the expiration date printed on your box really a drop-dead date?

Is the Expiration Date on Your Test Strip Box Accurate?

The truthful answer from the perspective of someone who is not a scientist or a doctor is, “Who knows? “Logic would dictate that the expiration date printed on your box of test strips cannot be the be-all and end-all and that there would likely be some wiggle room.

Look at it this way. The expiration date was put there by a reputable manufacturer who we must trust has done its due diligence in determining an expiration date. It is most assuredly erring on the side of caution to mitigate its own risk and liability. After all, the last thing a test strip manufacturer wants is problems due to people finding inaccurate readings when using its products, or worse, experiencing complications with their diabetes due to inaccurate glucose meter readings from test strips that have degraded.

So, we can assume that the expiration date on most test strips from reputable manufacturers is conservative. This is why it is easy to see why many people with diabetes might figure using a test strip an extra day or two or three, or even a week past the expiration date, isn’t such a big deal.

Maybe they’re right, but when you do a quick risk/reward analysis, is it worth taking chances? Yes, test strips are an expense those of us with diabetes have that those without the disease don’t, and saving money is always nice.

But we’re not talking about a jug of milk or a block of cheese. We’re talking about tools that are vital to our diabetes management and overall health every single day. Is it best to treat test strips with the latitude we give things that are not nearly as important to our health?

The Mayo Clinic Warns Against Using Expired Test Strips

None of us know exactly when a test strip will expire. Not all test strips are created equal. Different manufacturers use different enzymes and chemicals on their strips. Some of these probably last longer than others. Some probably hold up better than others when exposed to temperature fluctuations and other factors.

All we know is that all test strips, every single brand, will eventually become compromised. The best guess we’ve got to ensure that the ones we use are still viable is the manufacturer’s expiration date printed on the box.

From this perspective, it only makes sense to be mindful of the expiration date and stick to it. In fact, in a recent post by the Mayo Clinic, their medical experts agree. They recommended not using expired test strips to help prevent problems with your glucose meter.

The Risks of Buying Used Test Strips

Some people with diabetes look to save money by purchasing pre-owned diabetic test strips. The U.S. Food and Drug Administration (FDA) warns against this practice. The agency states that while these strips, while unused and appearing in good condition, may still pose a threat to the health of people with diabetes, as they may be expired or may not have been appropriately stored and, therefore, may not deliver accurate blood glucose readings.

Dr. Tim Stenzel, Director of the Office of In Vitro Diagnostics and Radiological Health at the FDA’s Center for Devices and Radiological Health, states, “We recognize that some people may be choosing to purchase pre-owned or unauthorized test strips because they believe there is cost savings. However, by doing so, they may be putting themselves at risk for serious injury or even death.”

Those are sobering words, to say the least. Even so, the debate about test strips and expiration dates will continue. As a leading online provider of test strips to valued customers nationwide, we encourage all our customers to err on the side of caution and guarantee that all diabetic test strips sold by Diabetic Warehouse will arrive at your home or office with plenty of lead time before the expiration date.


Your health is paramount.  Don't gamble with it by using expired test strips.  This article has equipped you with the knowledge to make informed decisions and prioritize accurate blood sugar readings for successful diabetes management.


At Diabetic Warehouse, we’re committed to helping those with diabetes manage blood sugar with a complete selection of testing and treatment supplies at up to 65% less than those found at most pharmacies and suppliers.