What Happens if You Swallow Mouthwash?

Everyone loves that fresh mouth feeling after a swish of mouthwash—but those ingredients that fight bad breath and kill bacteria can also be toxic if ingested.   

Although most mouthwash ingestion is not purposeful, many people can swallow some of it accidentally—or worse, maybe your child got into your medicine cabinet and thought it was a fun drink you’ve been hiding. 

If you or your child accidentally consumed mouthwash, here’s everything you need to know about the potential symptoms of mouthwash overdose, when to call a doctor, tips for using mouthwash safely, and the top ingredients that are toxic when ingested. 

What Happens if You Swallow Mouthwash?

While mouthwash is great for killing germs, freshening stale or bad breath, and fighting tooth decay or gum disease, it is certainly not great for drinking. 

Although the medicinal taste of most mouthwashes will deter people from drinking them, kids’ mouthwashes can have fun colors and sweet, fruity flavors that make them more appealing—or they may rifle through your medicine cabinet and drink your adult-intended mouthwash on accident.

Given their smaller size, any amount swallowed by a child could have a more serious effect than the same amount consumed by an adult. 

Therefore, if your child swallows mouthwash in any quantity, call the Poison Control Center immediately, where they will ask you details about which mouthwash they drank, how much, if they are experiencing symptoms, and the next steps to take. 

The Poison Control Center’s toll-free hotline is 800-222-1222, with operators available 24/7. 

If you’re an adult, swallowing a small quantity of mouthwash is unlikely to cause any significant adverse effects—but larger amounts could produce toxic effects like dizziness, drowsiness, trouble breathing, or convulsions in severe cases. 

So what constitutes “a little” versus “a lot”? When it comes to children, any amount of mouthwash consumed is considered potentially dangerous. 

As an adult, swallowing the small leftover amount in your mouth after you spit out your rinse or drinking water right after rinsing and taking the residual amount with it will be fine. 

While there is no recommended minimum amount of mouthwash that is safe to consume, if you manage to swallow more than the usual capful (perhaps by being distracted by pets or kids) or intentionally drink more than a capful, keep a close eye on any potential symptoms and be ready to call a doctor or the Poison Control Center or head to the Emergency Room.

Symptoms of Swallowing Mouthwash

Minor symptoms of swallowing a lesser volume of mouthwash might include:

• Digestive upset
• Nausea
• Throat irritation 

Severe symptoms of swallowing large quantities of mouthwash can cause symptoms similar to drinking alcohol excessively, including:

• Dizziness
• Slurred or slowed speech
• Increased heart rate or palpitations
• Vomiting
• Difficulty breathing
• Convulsions 

If dizziness, slurred speech, palpitations, or vomiting are noticed, call the Poison Control Center. Call 911 immediately if someone is experiencing difficulty breathing or convulsions, which are symptomatic of a mouthwash overdose.

It’s important to remember that you should not make yourself vomit if you swallow too much mouthwash.

When to Call a Doctor After Swallowing Mouthwash

If you are an adult and ingested a small amount of mouthwash, there’s likely no reason to panic. You may experience digestive issues or throat irritation, but you’ll probably be fine.

If you’re unsure, you can always call your doctor for their opinion based on the amount you consumed.

However, a more considerable amount (about two ounces/capfuls or more for adults) should warrant a call to the doctor and potentially the Poison Control Center, where they can instruct you further based on what mouthwash you drank and how much. 

If you experience any of the severe symptoms listed above, call your doctor, the Poison Control Center hotline, or 911 if the symptoms are life-threatening (convulsions or breathing problems). 

Similarly, a child who drank any amount of mouthwash will need to be treated immediately, as their bodies are smaller and cannot handle the same amount as adults. 

At the Emergency Room, the course of treatment for a mouthwash overdose depends on how much was ingested. Common treatment options might include: 

• IV fluid drip
• Laxatives to flush out the digestive system
• Activated charcoal, which helps to absorb the harmful chemicals
• Breathing support 

The bottom line is that if you’re unsure if you swallowed too much mouthwash, there is no harm in calling the Poison Control Center for more personalized advice.

Mouthwash Ingredients to Look Out For

The same ingredients that help kill bacteria and freshen breath can also be harmful if ingested. 

Alcohol-based mouthwashes (the kind that burns when you rinse) tend to be the most harmful when consumed. You may see alcohol listed as ethanol or ethyl alcohol on a label. 

When consumed, the most harmful and toxic mouthwash ingredients include:

• Ethanol (ethyl alcohol): Alcohol in mouthwash helps to solubilize the other compounds and acts as a vehicle to deliver active ingredients. It can cause dry mouth, weaken enamel, destroy beneficial oral bacteria, and might even increase the risk of oral, head, or neck cancer.
• Hydrogen peroxide: Used to whiten teeth and improve aspects of oral health.
• Chlorhexidine or chlorhexidine gluconate: Antibacterial agents commonly prescribed in cases of gingivitis or gum inflammation. 
• Methyl salicylate: A component of oil of wintergreen that acts as an antiseptic and is found in mouthwashes like Listerine. Swallowing large amounts of methyl salicylate can upset the body’s acid-base balance.
• Fluoride: A trace mineral thought to prevent cavities and tooth decay. 
• Cetylpyridinium chloride: An antimicrobial compound. 
• Menthol or eucalyptus essential oils: While essential oils are great for many things, some are not meant to be consumed. Many natural mouthwashes contain essential oils. 

Although kid-friendly mouthwashes typically do not contain alcohol, many still have fluoride or other ingredients that can upset their stomachs or cause other symptoms. 

Tips for Using Mouthwash Safely

If you have children, consider avoiding mouthwash until they are older and able to spit. The American Dental Association recommends that children under six not use mouthwash of any kind—even if it says it’s “kid-safe.”

When kids are old enough to start using mouthwash, they should always be supervised and monitored to ensure they do not swallow it. 

As an adult with kids, you should purchase mouthwash with child-resistant packaging and keep it on high shelves that your child cannot access.

Since 1995, mouthwashes containing at least 3 grams (0.11 ounces) of ethanol per package must have child-resistant packaging.

However, even an alcohol-free mouthwash can contain potentially harmful ingredients to children.

Accidentally Swallowed Mouthwash FAQs