What happens to your body when you take expired medicine

Medicines come with expiry dates to notify users when best to use them and when they are unsafe to use. But what happens to the body when you mistakenly ingest expired drugs?

A man taking expired medicines

From foods to drinks and every packaged edible, including drugs, consumers are encouraged not to consume anything that is out of date. This is for the sake of safety. 

In 1979, the US Food and Drug and Drug Administration (FDA) started requiring that drug makers put an expiry date on prescription and over-the-counter medicines. The expiry date is crucial for deciding whether a drug still works as intended or not.

A drug’s expiry date is usually found printed on the label or stamped on the carton or bottle. People must be careful to check for expiry dates before purchasing drugs as using expired medicines is risky and can cause harm to the health. 

What does the expiry date on drugs imply?

Medicines also have a shelf-life like most food items. But what exactly does the “Best Before” usually printed on drug labels, bottles, and cartons mean?

When drugmakers print expiry dates on medications, it means the day, month or year printed is the cut-off date for when the medicines are considered safe for use.

This means when the stated date reaches, the medicines are no longer safe to use. It is also the final day that drug makers guarantee the full potency of the drug. 

Photo by Laura James from Pexels

Note that the potency of drugs start decreasing starting from the moment they are manufactured. This means a drug’s potency doesn’t spontaneously disappear after its expiry date. 

After a drug’s expiry date, the medicine may still be potent; however, the date is only an assurance that its potency will last at least until that date. Whatever happens after that date, the manufacturer can no longer account for it.

Even 10 years after the expiration date, some medicines still retain some of their original potency. Placing a drug in a cool, dry place will help it retain its potency. 

It is similar to when you buy an electrical gadget, and it comes with a two-years warranty. The manufacturing company is only saying that it guarantees that all things being equal, the gadget will work perfectly fine within the two years.

If anything goes wrong within that period, the gadget can be returned, but the manufacturer won’t be held accountable for damages after two years. 

What happens when you take expired medicines?

Medicines undergo changes in their chemical makeup over time which can cause a reduction in their effectiveness. 

The expiry date is crucial for items that are susceptible to bacterial growth, such as medicines. Drugs can get contaminated with bacteria after expiration, thus, leaving a consumer susceptible to infections. 

Also, taking expired drugs increases the risk of antibiotic resistance. When you take an antibiotic that has lost some of its potency (expired), the medication will not treat infections effectively. 

Because the medication could not completely destroy the bacteria that invaded the body, the bacteria will transform, multiply, and come back in full force. When next you take the antibiotic, the bacteria would resist its actions.

Also, expired drugs can cause health complications giving rise to other diseases. In worst-case scenarios, they can cause harm to the kidneys and liver. There is the danger of developing allergies or having reduced immunity or changes in metabolism after taking expired medicines.

You can’t tell for sure whether an expired drug is still potent or not, but it is better to be safe than sorry. It is better to stock your medicine cabinet with fresh drugs and dispose of the expired ones.

What you should do if you mistakenly take expired medicine

Photo by National Cancer Institute on Unsplash

Don’t panic if you mistakenly take expired medication. Most times, taking expired drugs doesn’t mean you are dying just yet. It also doesn’t mean the drug will start reacting badly immediately.

Take the medicine back to the pharmacy for safe disposal and give a full report of why and when you took the drug. Your pharmacist will be better positioned to assess the situation and tell you what next to do. 

The best way to dispose of expired medicine

Expired medications shouldn’t be left lying around on the counter. This is because anybody, especially a child or an elderly person, can pick them and ingest them. 

According to the Centers for Disease and Prevention (CDC), about 50,000 children end up in emergency wards every year because they consumed medicines while an adult wasn’t watching.

You shouldn’t flush expired drugs down the toilet or the drain either. Drugs disposed of this way can make their way into the drinking water system. 

Some drugs come with specific disposal instructions; use that. Otherwise, mix the medicine with dirt, seal in a container and throw it into the trash. 


  1. American Medical Association. (2015). Pharmaceutical Expiration Dates. Report 1 of the Council on Scientific Affairs. July 25, 2001.
  2. Centres for Disease Control and Prevention (CDC). (2020). Put your medicines up and away and out of sight.
  3. The U.S. Food and Drug Administration (FDA). (2021). Don’t be tempted to use expired medicines.