Can Mouthwash Actually Expire?

In addition to routine brushing and flossing, a mouthwash rinse is a great way to round out your everyday oral health maintenance. Believe it or not, there are actually two different types of mouthwashes and each serves a different purpose, explains Byers Station Dental. Cosmetic mouthwashes provide a quick fix for bouts of bad breath by coating our mouths with pleasant flavors such as mint. The kind of mouthwash your dentist might recommend, however, is therapeutic mouthwash. Whether over-the-counter or by prescription, therapeutic mouthwashes are designed to help fight cavities, rid your mouth of bacteria, and protect against tooth decay — in addition to leaving you with delightfully fresh breath!

Depending on the type of mouthwash you're using, the ingredients may vary. However, some ingredients often found in mouth rinses include fluoride to prevent tooth decay, and peroxide for whitening purposes (via American Dental Association). Most mouthwashes are made up of water in addition to alcohol or another antiseptic, and that antiseptic will eventually begin to break down (per Bellevue Implant & Cosmetic Dentistry). Does that mean our mouthwash can actually expire?

In short, yes, mouthwash does expire. However, it can be hard to tell when exactly that expiration date is, since some mouth rinse products may not have an expiration date explicitly marked on the label, explains Bellevue Implant & Cosmetic Dentistry. Generally speaking, you can keep your mouthwash around for roughly two to three years after the manufacture date, according to Healthline. It's at this time that the alcohol or other antiseptic contained in the product will begin to break down. This ultimately leaves you with more water than alcohol, and it may even foster bacterial growth, which may be harmful.

Aside from potential exposure to bacteria, continuing to use mouth rinse long after it has expired ultimately doesn't do your teeth any favors. Your mouthwash will no longer clean your teeth, fight off tooth decay, or leave your breath feeling minty fresh in the way it once did (via Healthline). Even before the expiration date, however, if you notice a change in the color, smell, or texture of your mouthwash, it's best to discard it.

If your mouth rinse lists an expiration date, be sure to throw it out by that time for your own health and safety. If you can't find an expiration date listed on your mouthwash product, experts at Bellevue Implant & Cosmetic Dentistry suggest marking the bottle with the date that you bought the mouthwash and then throwing it out within two to three years from that date.