Hydrogen peroxide is a common household product that many people use for disinfecting wounds, whitening teeth, and sanitizing surfaces. Some people also use dilute hydrogen peroxide as a mouthwash or gargle. But is rinsing with hydrogen peroxide safe or could it potentially cause harm?
What is hydrogen peroxide?
Hydrogen peroxide (H2O2) is a chemical compound made up of two hydrogen atoms and two oxygen atoms. In its pure form, it is a colorless liquid. In dilute concentrations, such as the 3% solution sold in pharmacies, it appears as a clear, colorless liquid.
Hydrogen peroxide works as a disinfectant and whitening agent through the process of oxidation. When it encounters organic material like bacteria, viruses, or stains, the extra oxygen atom splits off and destroys the organic matter. This releases oxygen gas, which bubbles up, giving diluted hydrogen peroxide its characteristic fizzing.
How is hydrogen peroxide used?
Some common uses of dilute hydrogen peroxide include:
- Disinfecting minor cuts, scrapes, and burns
- Treating mouth injuries
- Tooth whitening and oral hygiene
- Sanitizing surfaces
- Whitening laundry
- Cleaning produce
Hydrogen peroxide can be used undiluted or in solutions ranging from 3% to 10% for household applications. Stronger solutions up to 30% may be used in some dental office procedures.
Is hydrogen peroxide mouthwash safe?
Hydrogen peroxide is sometimes used as an antiseptic mouthwash or gargle. Dilute solutions of 1.5% to 3% hydrogen peroxide are typically recommended for this purpose.
Proponents claim that hydrogen peroxide mouthwash can:
- Kill bacteria that cause bad breath
- Treat gum disease
- Whiten teeth
- Prevent plaque buildup
However, there is debate over whether hydrogen peroxide mouthwash is safe and effective for regular long-term use.
Potential benefits
Here are some of the potential benefits of using hydrogen peroxide as a mouthwash:
- Kills bacteria – Hydrogen peroxide is an effective disinfectant that can kill bacteria in the mouth linked to bad breath, gum disease, and tooth decay.
- Whitens teeth – Hydrogen peroxide is a mild bleaching agent that may brighten and remove surface stains from teeth with regular use.
- Removes debris – The bubbling action of hydrogen peroxide can help dislodge food particles, loosen plaque, and clear mucus.
Potential risks and side effects
However, there are also some potential downsides to consider:
- Mouth irritation – Hydrogen peroxide can cause temporary mouth irritation, especially with higher concentrations. Stinging, soreness, and white patches in the mouth have been reported.
- Tooth enamel damage – Frequent exposure to peroxide may damage tooth enamel over time by depleting antioxidant reserves.
- Gum irritation – Hydrogen peroxide has been linked to gingivitis (gum inflammation) when used long-term.
- Upset stomach – Accidentally swallowing hydrogen peroxide can cause nausea, vomiting, and other GI symptoms.
Overall, limited research is available on the safety and efficacy of hydrogen peroxide as a daily mouthwash. While generally recognized as safe for short-term use, regular long-term use is more controversial.
What concentration of hydrogen peroxide is safe for gargling?
Most sources recommend using a 1.5% to 3% hydrogen peroxide solution for gargling purposes. Here are some general safety guidelines for concentration levels:
- 1.5-3%: Safe for daily use as a mouthwash or gargle.
- 3-6%: Appropriate for short-term use for mouth infections or whitening. Do not use for more than a week.
- 10%: Not recommended for mouthwash use due to high risk of oral irritation.
- Above 10%: Severe oral burns can occur with higher concentrations.
When using hydrogen peroxide as a mouthwash, it should always be properly diluted rather than used in its full-strength form, which is caustic at concentrations over 10%.
Hydrogen peroxide gargle guidelines
Here are some tips for using hydrogen peroxide as an oral rinse safely and effectively:
- Dilute concentrated peroxide to a 1.5-3% solution.
- Use no more than 15-20mL of dilute solution for gargling.
- Rinse mouth with plain water after gargling to remove residue.
- Limit use to 1-2 times daily at most.
- Do not swallow hydrogen peroxide solution.
- Discontinue use if irritation develops.
- Keep out of reach of children.
It’s also best to consult your dentist before using hydrogen peroxide long-term.
Does hydrogen peroxide kill good oral bacteria?
Hydrogen peroxide is a broad-spectrum antimicrobial agent. This means it indiscriminately kills many types of bacteria, viruses, and fungi. Unfortunately, this includes both good and bad microorganisms.
Research shows that hydrogen peroxide can damage or kill beneficial oral bacteria that help maintain dental and gum health, such as:
- Streptococcus sanguinis – Helps prevent tooth decay
- Streptococcus salivarius – Produces bacteriocins that fight infection
- Lactobacillus species – Keep pH neutral and hinder cavities
With regular use, hydrogen peroxide may disrupt the natural balance of microflora in the mouth, leading to negative effects. More research is still needed though.
Does hydrogen peroxide damage gums?
There are some concerns that frequent use of hydrogen peroxide as a mouthwash may irritate gum tissues and contribute to gingivitis (gum disease). However, the evidence is not conclusive.
Potential ways that hydrogen peroxide could affect gums include:
- Direct irritation – Hydrogen peroxide can cause temporary whitening and soreness of oral mucosa.
- Healthy bacteria depletion – Killing too many good oral bacteria can compromise gum health.
- Enamel erosion – Weakening tooth enamel may make gums more prone to irritation.
That said, hydrogen peroxide does appear to attack the types of bacteria most implicated in periodontal disease, such as Prevotella intermedia and Fusobacterium nucleatum. One study found no significant difference in gingivitis between a hydrogen peroxide group and a placebo group when used for 4 weeks.
More clinical research on larger sample sizes is needed to determine hydrogen peroxide’s effects on gums with long-term use.
Should you rinse your mouth with hydrogen peroxide every day?
Daily use of hydrogen peroxide as an oral rinse is somewhat controversial. Some dentists recommend against using it for longer than 1-2 weeks at a time due to limited evidence on safety and concerns about side effects.
Potential downsides of rinsing daily with hydrogen peroxide include:
- Damage to healthy oral bacteria
- Gum irritation with prolonged use
- Tooth enamel erosion over time
- Oral mucosa irritation
- Altered taste sensation
However, some studies suggest that hydrogen peroxide mouthwash is well tolerated when used once or twice daily for at least 4 weeks. More research is still needed on longer-term daily use.
Talk to your dentist before beginning a daily hydrogen peroxide gargling regimen, especially at higher concentrations over 3%. They may recommend limiting use to 1-2 weeks at a time with periodic breaks.
What are the signs of hydrogen peroxide poisoning?
Hydrogen peroxide poisoning is rare but can occur if it is swallowed at high concentrations. Here are signs and symptoms to watch for:
- Nausea, vomiting
- Abdominal pain, diarrhea
- Low blood pressure
- Dizziness, fainting
- Blisters or burns in throat and stomach
- Bleeding gums
- Difficulty breathing
- Altered heartbeat
- Seizures
- Coma, death (in severe cases)
Seek immediate medical attention if poisoning is suspected after swallowing or inhaling concentrated peroxide solutions.
Tips for safe use of hydrogen peroxide rinse
Here are some tips for safely using hydrogen peroxide as an oral rinse:
- Always dilute concentrated hydrogen peroxide to a 1.5-3% solution.
- Use no more than 1-2 times daily.
- Limit use to 1-2 weeks at a time.
- Rinse mouth thoroughly with water after use.
- Don’t use if you have mouth injuries or irritation.
- Don’t swallow hydrogen peroxide solutions.
- Keep out of reach of children.
When used properly in moderation, hydrogen peroxide can be a safe, effective addition to an oral hygiene regimen. But be cautious with long-term use and consult a healthcare professional if you have concerns.
The bottom line
Hydrogen peroxide is an effective disinfecting mouthwash that may provide certain benefits when used occasionally. However, regular long-term use is more questionable due to limited evidence on safety and potential drawbacks.
Most experts advise limiting hydrogen peroxide gargling to short periods of 1-2 weeks at a time. Higher concentrations above 3% should not be used daily.
Overall, hydrogen peroxide mouthwash appears relatively safe when used properly in moderation. But more research is still needed to establish definitive guidelines for regular daily use.