Why Does Mouthwash Burn When I Use It?

Does using mouthwash cause a burning sensation in your mouth? Find out why it happens and what you can do about it with this guide from Flossy.

January 11, 2022
Why Does Mouthwash Burn When I Use It?

In most mouthwash commercials, the burning sensation is advertised as a sign that the product is killing bacteria and freshening up your breath. 


While there’s a degree of truth to this, a burning sensation doesn’t always mean the product is doing its job. Plus, if it burns, you’ll be much less likely to use the mouthwash, which pretty much defeats the whole purpose of buying a mouthwash in the first place.


To keep your oral hygiene routine undisturbed, we created this guide to mouthwash. Read on to find out why some types of mouthwash can cause a burning sensation, the best alternatives to traditional oral rinses, and our best tips for using mouthwash. 


The Benefits of Using Mouthwash

The benefits of mouthwash largely depend on what kind we’re talking about. Generally speaking, there are two types of mouthwash: cosmetic and therapeutic. 


Cosmetic rinses are meant to mask bad breath and leave your mouth with a pleasant taste. These are more commonly available over-the-counter and tend to have mild effects. Therapeutic rinses, on the other hand, are where most of the benefits occur. Here are some of the benefits of using a therapeutic mouthwash. 


  • Reduce Plaque: Most therapeutic rinses contain chlorhexidine digluconate, an antiseptic that’s considered the gold standard for reducing plaque—a thin layer of bacteria that forms on the teeth. Chlorhexidine digluconate works by penetrating the plaque and killing its superficial layers. 


  • Neutralize Acidity: Too-high acidity can break down the enamel, the protective outer layer of our teeth. Some therapeutic rinses can neutralize the pH of the mouth, making it less acidic and thus, less damaging to the teeth. 


  • Provide Dry Mouth Relief: Some therapeutic rinses contain xylitol, which improves saliva production and relieves some of the symptoms of dry mouth. 


  • Soothe Canker Sores: Mouthwash that contains antiseptic ingredients can bring some relief to canker sores by reducing the number of bacteria that cause irritation.


  • Strengthen Teeth: Many therapeutic rinses contain fluoride, which works with the minerals in your saliva to create a protective coating on your teeth that helps to prevent tooth decay. 


Rinsing regularly has been shown to fight against the common cold. This, combined with the above benefits, is what makes the right mouthwash an important part of your oral hygiene routine. 


Why Does Mouthwash Burn?

There are several reasons why your mouthwash may burn, which can be roughly split up into two categories: irritating ingredients and oral conditions that make you more sensitive to your mouthwash. 


Common Mouthwash Ingredients

Alcohol: It’s a common misconception that alcohol is used in mouthwash for its antiseptic properties. But the truth is that most oral rinses don’t contain enough alcohol to make any difference in disinfection. And the reason alcohol is used is that it acts as both a preservative and a carrier agent for flavors such as menthol. Nonetheless, it’s still very likely to cause burning in your mouth, especially around the tongue where your taste buds are located. 


Chlorhexidine: Chlorhexidine is the gold standard for sanitization, which makes it one of the most effective solutions for breaking up dental plaque. But while it’s incredibly effective, it can cause irritation in some people. Make sure to check with your dentist if you think that this ingredient is causing your mouth to burn. 


Menthol: Perhaps one of the most common ingredients in mouthwashes, menthol is derived from peppermint. It makes for a great bad breath remedy because, well, it smells and tastes great. Aside from that, it has antimicrobial properties that make it ideal for killing oral bacteria. However, some people can be sensitive to menthol, which can manifest as a burning sensation instead of the slight tingling feeling we desire from our oral rinse. 


Common Oral Conditions

If rinsing with a mouthwash is a new problem that you’re experiencing, then it’s very likely that you might have developed an oral condition that is making you more sensitive to common mouthwash ingredients. Conditions such as ulcers, cold sores, or an abrasion from excessive brushing can make your mouth tender and sensitive to common mouthwash ingredients. You may also begin to experience tooth sensitivity. 


If you suspect that you’re experiencing any of these conditions, it’s important to make an appointment with a skilled dentist to get to the root cause of the problem. 


Best Non-Burning Mouthwash

Even if you’re sensitive to common mouthwash ingredients, we certainly don’t want you to skip out on this important part of your oral hygiene routine. Here are four alternative oral rinses that you can use without feeling any burning.


1. Alcohol-Free Mouthwash

If alcohol causes burning that’s too much to handle, then it’s best to avoid this ingredient. (Trust us, you won’t be missing out on any antiseptic benefits!) A mouthwash labeled “alcohol-free” is your best bet. And if menthol also causes a burning sensation, then it’s also possible to find a mouthwash that’s labeled “fragrance-free.”


2. Coconut Oil

Coconut oil has been used for millennia in Ayurvedic medicine due to its antibacterial properties. In addition, it’s an all-natural and non-toxic product that tastes great. You can either rinse with a spoon of coconut oil (which will melt quickly in your mouth) or buy a coconut oil rinse that’s already in liquid form. 


3. Essential Oils

Various essential oils have been shown to have antibacterial properties. Aside from peppermint, we also appreciate tea tree oil, eucalyptus, thyme, cinnamon, and lemon. You can easily make an at-home oral rinse by combining a few drops of your favorite essential oils with water and salt. 


4. Saline Rinse

This is the simplest oral rinse that you can make anywhere in the world with just salt and warm water—a perfect solution for frequent travelers. Salt is known for its healing properties, which is why it's recommended for use after tooth extractions. However, you can gargle with it even if you aren’t experiencing any ailments. 


Best Practices for Using Mouthwash

Using mouthwash may seem like a pretty straightforward activity, but there are actually right and wrong ways to do it. Here are some of our top tips for making sure you’re using mouthwash in the best way. 


1. Rinse Before Brushing

In general, it’s better to use mouthwash before you brush your teeth. This is because your toothpaste can contain active ingredients such as fluoride that need to be left on your teeth (and not rinsed off) in order to do their work. However, if your mouthwash contains therapeutic ingredients, then it might be best to rinse afterward. In this case, it’s always best to consult with your dentist. 


2. Use the Right Amount

If you use too little mouthwash, you might not get its full benefits. However, using too much can cause you to swallow some of it, which can definitely be unsafe. For this reason, it’s always a good idea to use the cap that your mouthwash comes with and to measure out the recommended amount (this shouldn’t equate to more than one ounce of mouthwash).


3. Rinse for at Least One Minute

Although it’s best to follow the directions on your mouthwash bottle, we recommend rinsing for at least one minute. This will ensure that you’re able to reach all the sides of your mouth with the rinse while letting the active ingredients do their work. 


4. Get All the Nooks and Crannies

Make sure to swish the mouthwash back and forth in your mouth, reaching all areas from your back wisdom teeth to the tops of your gums. And as the last step, make sure to gargle before spitting out the mouthwash. 


5. Discontinue Use if Necessary

If your mouthwash is causing excessive burning or discomfort, then it’s best to just stop using it. A mouthwash that you’re sensitive to can break down some of the tissue in your mouth, which can lead to greater problems down the line. And in either case, there’s no reason to use something that feels unpleasant when there are tons of gentle mouth rinses available to you. 


Rinsing Should Be Fun

A mouthwash can cause burning because it contains certain ingredients you’re sensitive to or because you’re experiencing oral conditions that make your mouth a bit more sensitive. Make sure to check with your dentist to make sure that everything is fine healthwise. 


And if the burning continues, then there are plenty of alternative oral rinses that will be just as effective (but much more fun) to use. 



Our Sources:

Mouthwashes: Do They Work and Should We Use Them? Part 1: Antiplaque Efficacy of Mouthwashes | NCBI 

The Antimicrobial Activity of Thyme Essential Oil Against Multidrug-Resistant Clinical Bacterial Strains | NCBI 

Oil Pulling for Maintaining Oral Hygiene – A Review | Science Direct

Gargling for Coronavirus? What Science Can Tell Us | The New York Times