Man holding throat in pain

Why does mouthwash burn, or feel like it does?

Mouthwash is an effective part of a thorough oral hygiene routine, but it can sometimes come with an unpleasant sensation – burning. When it feels like your mouthwash burns the tongue or gum areas, it can put you off using it at all. So, why does mouthwash cause a burning sensation?

In this article, we’ll help you get to the root of the issue and advise on what changes you can make, like switching to a milder mouthwash, so you can continue to enjoy that fresh feeling - minus the burning sensation.  

Burning sensation? Possible effects of alcohol in mouthwash

If it feels like your mouthwash burns the tongue or gum areas, then the most likely cause is the alcohol (ethanol) in the formulation. It’s the most common agent in mouthwash responsible for that burning feeling that’s typically experienced on the tongue and gums. However, alcohol in mouthwash is perfectly safe, and some people enjoy that extra-clean sensation!

The logical conclusion is to go for a mouthwash with 0% alcohol. But an alcohol-free formulation isn’t automatically the same thing as a no-burn mouthwash. Why do even alcohol-free mouthwashes sometimes cause a burning sensation? There are a couple of other ingredients that could be involved.

Why can an alcohol-free mouthwash cause a burning sensation in the mouth?

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When a mouthwash causes a burning sensation, it isn’t always down to the alcohol content. Some mouthwashes contain chlorhexidine, which is an antiseptic agent.

Dentists might prescribe a mouthwash with this ingredient if you have poor gum health and, while some people find this kind of formulation to be an effective no-burn mouthwash, it can cause irritation in some people’s mouths. So, when mouthwash feels like it is burning your mouth, check for chlorhexidine in the list of ingredients, and speak with your dentist about alternatives if it’s been prescribed for a specific condition.

Why can mouthwash cause discomfort? Exploring sodium lauryl sulfate sensitivity

In the case of products that don’t contain alcohol or chlorhexidine, but still cause discomfort, why can using mouthwash cause a burning sensation? It could be that sodium lauryl sulfate (SLS) is involved. SLS is a foaming agent (surfactant) that is widely used in oral care products to aid cleaning and the removal of plaque and stains.

Sodium lauryl sulfate has been found to be perfectly safe by Global Regulators and safety experts2, and some people like the mouth feel it produces. The majority don’t experience any side effects from SLS in oral hygiene products. However, some people with delicate oral tissues can find that this ingredient irritates the skin inside the mouth, particularly if they suffer from recurrent mouth ulcers.

When to seek dental advice

There may be several reasons as to why you are experiencing a burning sensation when using mouthwash. The best thing to do in this situation is to stop using the specific mouthwash and consult your dentist, who can rule out other causes and perhaps recommend a different mouthwash.

Alcohol and SLS-free Mouthwash

Mouthwash plays an essential role in a healthy oral routine, so it’s important to find one that works for you. Try a mouthwash that does not contain sodium lauryl sulfate or alcohol to help reduce the chances of oral discomfort and burning. As Dentist Surina Seghal comments:

Oral care products without sodium lauryl sulfate can be beneficial for various reasons. Additionally, patients with a delicate oral mucosa, especially those with aphtous ulcers, find sodium lauryl sulfate products less suitable.
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Dentist Surina Seghal

Zendium’s Complete Protection Mouthwash contains 0% alcohol and 0% SLS. The mild mouthwash is gentle on the delicate tissues in the mouth and doesn’t alter your sense of taste after usage. It contains natural enzymes and proteins to boost the mouth's natural defences, as does Zendium’s toothpaste, also without sodium lauryl sulfate – so you can use that alongside Zendium’s mouthwash without sodium lauryl sulfate.

Woman holding Zendium Mouthwash


1 NCBI – Comparative Evaluation of Antiplaque Efficacy

FDA – Code of Federal Regulations Title 21

4 Dental Review – Dr Surina Sehgal: Why Choose SLS-free Toothpaste?

The advice in this article does not constitute medical advice; it is solely available for information purposes. We recommend that you consult your dentist if you are experiencing any tooth or gum problems.