When do medicines expire? When do medicines expire?

When do medicines expire?

Before 22 November, 2016 Ana María López de Mesa


It is normal for people to not throw away commonly used medicines or medicines for small emergencies that can occur at home.

In most cases, they remain in the medicine cabinet for a long time after they are used just a few times, which is when people begin to wonder if these medications will be effective the next time they are used or if they may be harmful to their health.

The first thing that needs to be clarified is that just because their expiration date has passed, not all medications become a potential health threat. In fact, many of them continue retaining a large degree of their pharmaceutical properties. After this date has passed, however, they can begin to slowly lose these properties, which is why the manufacturer is only responsible for their effectiveness up to that point.

A decade ago, the American Medical Association (AMA) found that most medicines can last longer than their expiration dates.

What has been found is that after they have been opened, medications are more susceptible to conditions such as humidity, temperature, light, etc. Their deterioration process changes, however, depending upon the unique properties of each medication. The following are answers to some of the most common dilemmas:

  • Alcohol’s shelf life is more than five years. It can become contaminated by external components, however.
  • Iodine begins to lose its effectiveness after it is opened and the higher the temperature it is exposed to, the faster it loses its effect.
  • Hydrogen peroxide can also last up to five years. A way to help determine whether it is effective is if white foam appears when it comes into contact with a cut.
  • Once acetaminophen has been opened, it should be used before it reaches the expiration date indicated on the package. If it has not been taken out of its casing, however, it can last for up to five years.