Does Mouthwash Expire?

If the milk in your ref is a bit past its expiration date, what do you do? Most likely, you'll sniff the milk to judge its freshness and decide whether to drink it or toss it. Food expiration dates refer to the last date the item is guaranteed to be at its peak — not when you should throw it out.

So, what about cosmetic and drug products — or items straddling both categories? Should you pay close attention to when those products expire? We'll give you the info on non-food product expiration dates, including products like mouthwash. And we'll let you how to handle expired oral care items.

Understanding Expiration Dates

As it turns out, expiration-date rules are a bit different for items other than food, such as mouthwash and toothpaste. While Consumer Reports notes that expiration dates on food (except infant formula) aren't regulated, the Food and Drug Administration (FDA) does regulate the expiration dates on any drugs or cosmetic products categorized as drugs.

Cosmetics regulated as drugs are ones formulated to treat or prevent a condition, notes the FDA. These personal care products must be tested for stability and require an expiration date printed on the packaging.

For instance, when you look at an expiration date on a bottle of mouthwash, you have an idea of how long the ingredients in the bottle will stay stable- which means the FDA identified how long the mouthwash would work as intended. But not all mouthwashes are created equal.

Does Mouthwash Expire?

To understand expiration dates on mouthwashes, you first need to know that the FDA and the American Dental Association (ADA) divide mouthwash into two categories: therapeutic and cosmetic.

Cosmetic Mouthwash: This type of mouthwash can help mask bad breath. But it's not going to correct dental concerns, such as gum disease, enamel wear, tooth decay, plaque buildup, or dry mouth. If you're looking for a mouthwash that helps control or correct specific problems, you'll want a therapeutic mouthwash.

Although the FDA doesn't control cosmetic mouthwashes, you'll still want to be cautious about their expiration dates. It's likely a cosmetic mouthwash will decline in quality the longer it sits on your bathroom shelf.

Therapeutic Mouthwash: These mouthwashes contain active ingredients the FDA regulates, such as those listed by the ADA: fluoride, peroxide, essential oils, cetylpyridinium chloride, and chlorhexidine.

If you have an old bottle of therapeutic mouthwash lying around, it's essential to pay attention to its expiration date. If the bottle is past its prime, it's likely the active ingredients have started to lose their effectiveness.

It's too bad you can't give mouthwash the sniff test as with milk to determine if you should throw it out. Just be aware that using therapeutic mouthwash past its expiration day means it won't be able to do the job as well as it could when it was fresh off the shelf.

What Happens If You Use Expired Mouthwash?

As the FDA explains, once the expiration date on a product has passed, there's no way to guarantee it'll be effective. Fluoride is an essential active ingredient in therapeutic mouthwash. A study published in Brazilian Oral Research examined fluoride stability in toothpaste and found that soluble fluoride concentration in toothpaste decreased over time, making the toothpaste less effective at fighting cavities. Although this article is talking about mouthwash, fluoride is fluoride!

So, all the benefits you can receive from therapeutic mouthwash will go down the drain if you use an expired product.

To retain your mouthwash's effectiveness, store it in a cool, dry, and dark place — such as your medicine cabinet. Unlike milk, mouthwash takes much longer to expire. By storing mouthwash properly, it should last up to two or three years, depending on its expiration date.

All in all: yes, mouthwash eventually expires — especially therapeutic ones. If you find a dusty bottle of expired mouthwash, your best bet is to discard it or ask your pharmacist or dentist for advice. If your dentist prescribes you a mouthwash to treat any oral condition, use it as directed before it expires. Contact your dental provider if you think you need a replacement. It never hurts to be cautious! With the freshest possible mouthwash, you have a better chance of making your mouth healthy and happy.