The Truth About Expired Polymyxin B Sulfate And Trimethoprim

Trimethoprim SulfatePolymyxin B


As we all know, antibiotics are essential in treating bacterial infections. Polymyxin B sulfate and trimethoprim are two commonly prescribed antibiotics. However, what happens when they expire? Do they lose their effectiveness? Can they be harmful? In this article, we will explore the truth about expired polymyxin B sulfate and trimethoprim.

What Happens When Antibiotics Expire?

Antibiotics, like any other medication, have an expiration date. This date is determined by the manufacturer and is based on a variety of factors, such as the stability of the ingredients and the expected potency of the drug over time. Once an antibiotic has passed its expiration date, it may not work as well as it did when it was new.

Is it Safe to Use Expired Antibiotics?

While it is generally safe to use expired antibiotics, it is not recommended. The effectiveness of the drug may be reduced, and it may not be strong enough to fight off the infection. Additionally, expired antibiotics may contain harmful bacteria that can cause serious health problems.

What Happens When You Take Expired Polymyxin B Sulfate and Trimethoprim?

Taking expired polymyxin B sulfate and trimethoprim can be dangerous. The drugs may not be effective in treating your infection, and they may even cause harm. Expired antibiotics may contain harmful bacteria that can cause serious health problems.

How to Properly Dispose of Expired Antibiotics

If you have expired antibiotics in your medicine cabinet, it is important to dispose of them properly. Do not flush them down the toilet or throw them in the trash. Instead, take them to a pharmacy or a drug take-back program. These programs will safely dispose of your expired medications.


In conclusion, expired antibiotics, including polymyxin B sulfate and trimethoprim, may not be effective in treating bacterial infections. They may even be harmful. It is important to properly dispose of expired antibiotics and to always follow your doctor’s instructions when taking medication. If you have any questions or concerns, speak to your healthcare provider.