Expiration/Best By Date: Is It Safe To Use Expired Medicines?

Every once in a while, to calm a mildly aching head, we reach for the medicine cabinet and pop a pill. Later, while reading the packaging, we realize that the pill has passed its expiration date!

you’ve taken an expired medicine meme

Expiration dates are a major cause of concern among manufacturers and consumers alike, probably more so in the latter. The question is, what do those dates signify after all? Are your days numbered if you mistakenly pop an expired pill or consume an expired biscuit?

What is an Expiration date?

When buying products at the supermarket, you surely must have noticed the label (usually at the bottom or side of the packaging) that says ‘Best Before’, ‘Best By’ or ‘Use By’ followed by a date, or on some products, you might actually find the words ‘Expiration date’. This date holds a great deal of significance, as it’s the final date up to which the manufacturer vouches for full potency of the medicine (and its ingredients) and promises that it can be safely used, if prescribed by a medical professional.

medicine capsule on white background

Photo Credit : Isara Kaenla / Shutterstock

Putting an expiration date on drugs became a legal necessity for pharmaceutical manufacturers in the United States when a law was passed in 1979. However, what started out as a legal requirement arguably became one of the biggest tools that manufacturers use to drive their sales.

How is an expiration date determined?


After the main clinical trials of a drug are over and it’s deemed fit for use, a set of standards are determined to estimate how long a drug will retain its potency after its date of manufacture. To see how stable a drug is and how long it will hold up before becoming ineffective, it’s passed through a series of tests, including short-term exposure to extreme humidity, heat, light and oxidation.

This not only helps to determine the stability of the drug, but also helps to identify degradation pathways – different ways you can expect a given drug to deteriorate over time. After taking all of this into account, the manufacturer stamps a date on the drug beyond which the potency of the drug can no longer be guaranteed.

Food Items

edible products

Common food items come with an expiration date (Photo Credit : ValeStock / Shutterstock)

To determine the expiration date of a food item (like dairy products, culinary items etc.), manufacturers either deploy their own R&D teams or hire expert firms to perform ‘storage studies’ on the item and provide an expiration date. These firms first determine the timeline of the study by establishing an estimate on the life of similar items, looking at how long the ingredients are going to last and the expected conditions in which the product is going to be stored once it is out in the market.

Unlike medicines, food items are not put through rigorous tests to determine their expiration date. Instead, they are labelled, stored in simulated conditions of varying humidity, heat and light, and then left undisturbed for some time (a pre-defined duration). After that period of time has passed, the samples are examined and, after looking at the observations and various parameters used during the study, an expiration date is settled on.

Is it safe to consume medicines/foods after they’ve ‘expired’?


Medicine expired date

Photo Credit : EM Karuna / Shutterstock

According to a study (Shelf Life Extension Program) conducted by the American Medical Association (AMA), it was found that the actual shelf lives of most drugs are much longer than what the expiration date would lead you to believe. A few of the many drugs that can be extended beyond their original expiration dates included amoxicillin, morphine sulfate, diphenhydramine, ciprofloxacin and most of the common pills used for mild headaches and fever.

However, there are also some medications, including insulin (to control blood sugar), oral nitroglycerin (NTG) and vaccines that are prone to quick degradation. Therefore, it’s difficult to determine which drugs will still be effective after their expiration date, so to be on the safe side, it’s usually recommended to avoid taking drugs that have ‘expired’.

Food items

a lady checking expiration date

It’s a good practice to check a product’s expiration date before buying it (Photo Credit: eldar nurkovic / Shutterstock)

As with medicines, most food items (at least the ones we use on a daily basis) won’t necessarily harm your health after passing their expiration dates. You can expect ‘expired’ foods to not taste as good as the ones fresh out of the factory, but they certainly won’t cause any harm after sitting in your fridge a few weeks after the expiration date.

Contrary to popular belief, expiration dates on food articles aren’t a measure of their safety; in fact, they represent the time after which the articles shouldn’t be expected to be at their peak freshness and quality.

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As it turns out, expiration dates DO indicate the potency of drugs and the freshness of food items, so they should always be checked before purchase, but if you unwittingly consume something after it has overshot its expiration date by a few days, don’t worry about any deadly side effects!

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About the Author

Ashish is a Science graduate (Bachelor of Science) from Punjabi University (India). He spends a lot of time watching movies, and an awful lot more time discussing them. He likes Harry Potter and the Avengers, and obsesses over how thoroughly Science dictates every aspect of life… in this universe, at least.

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