Hydrogen Peroxide for Teeth Whitening: Is It Safe?

Hydrogen peroxide (HP) is a popular whitening agent found in many household items, such as cleaning products, antibacterial mouthwashes, and natural bleaching products.

It’s also used in professional in-office treatments and over-the-counter teeth whitening products. It works by targeting stain molecules in and around a surface to restore a whiter appearance.

Is Hydrogen Peroxide Safe for Teeth?

Hydrogen peroxide is safe for teeth when used correctly, which mainly depends on the concentration of the product and how it is applied.

It’s safe for teeth at 2% or less concentration. Studies show that concentrations lower than 2% won’t damage hard or soft oral tissues.

You can use it in self-administered oral health care products like mouth rinses. However, you should always follow your doctor's safety guidelines or the product’s instructions.

Other Benefits of Hydrogen Peroxide for Teeth

Hydrogen peroxide has additional benefits for teeth beyond its whitening abilities. Other positive effects hydrogen peroxide can impart on your oral health include:

• Antibacterial properties that can help mild cases of gum disease
• Reduce inflammation
• Soothe a sore throat
• Disinfect your mouth

How Does Hydrogen Peroxide Whiten Teeth?

Hydrogen peroxide acts as a bleaching agent that breaks apart stains and lifts them out of your enamel. It oxidizes your teeth without causing significant changes in tooth enamel.

You’ll typically apply tooth whitening products that contain HP to your teeth for a set amount of time. Letting the treatment sit on your teeth allows hydrogen peroxide to oxidize the stains.

At-home teeth bleaching products typically contain 5 to 10% hydrogen peroxide or 35% carbamide peroxide. You’ll wear them for 10 to 30 minutes over multiple days.

How to Use Hydrogen Peroxide for Teeth Whitening

Hydrogen peroxide is very effective at whitening teeth. Studies show that treatments containing HP are more effective at whitening teeth than non-peroxide treatments.

Fortunately, there are multiple ways to whiten your teeth with HP:

In-Office Treatments

Most local dentists offer in-office teeth whitening treatment. Professional teeth whitening costs more than DIY or OTC treatments but will have more dramatic results.

The main difference between in-office treatment and over-the-counter products is that your dentist will use a much higher hydrogen or carbamide peroxide concentration.  However, it will be more expensive than an at-home option.

On the other hand, you’ll need fewer treatments thanks to the higher concentration of active ingredients. You’ll also benefit from professional supervision in case of sensitivities or allergic reactions.

Over-the-Counter Treatments

Several over-the-counter methods for whitening your teeth at home are safe and effective. These products include:

• Teeth whitening kits — These kits typically include a whitening gel containing hydrogen peroxide and a tray that you insert into your mouth. 
• LED whitening kits — These are similar to teeth whitening kits, but they use an LED light to speed up the whitening process. This is better for people with sensitive teeth.
• Teeth whitening strips — A piece of plastic coated in whitening gel that you apply to your teeth. 
• Whitening toothpaste — A type of toothpaste that contains hydrogen peroxide. It’s not as effective and typically only affects external stains.
• Hydrogen peroxide mouthwash — To avoid adverse effects like burning or pain, ensure the mouthwash contains 3% or less hydrogen peroxide.

When using whitening strips or gels, use 3 to 10% of hydrogen peroxide. Lastly, consult your dentist before use and follow the instructions for each product carefully.

DIY Treatments

Although DIY treatments can be effective when done correctly, we don’t recommend them. There’s a higher risk of adverse effects when using DIY methods. 

There are two ways people use hydrogen peroxide to whiten their teeth at home. We’ll go over how to do them properly and discuss the risks associated with them:

Hydrogen Peroxide Rinse

Here’s a quick step-by-step guide to making a hydrogen peroxide rinse:

• Mix hydrogen peroxide with water at a 1:1 ratio
• Swish the mixture in your mouth for 30 seconds to 1 minute
• Spit out the solution
• Don’t swallow it

You can rinse with hydrogen peroxide a few times weekly to see results. However, it can cause an upset stomach, vomiting, or throat irritation.

Using a rinse with a higher concentration of hydrogen peroxide can also lead to severe stomach irritation and burns.

Hydrogen Peroxide Paste

Here’s how you can make a hydrogen peroxide paste at home: 

• Put two or three teaspoons of baking soda in a bowl with a splash of hydrogen peroxide
• Mix the substances with a clean spoon until you get a smooth, thick paste
• Use a toothbrush to rub the paste directly on your teeth in small circles before leaving it on for two minutes
• Rinse off the paste by swishing water in your mouth several times

A gas embolism can also occur if you ingest a large amount of hydrogen peroxide, as the resultant air bubbles block the blood vessels.

Although it’s very rare, this condition can be life-threatening. Seek emergency medical attention if you suspect you have a gas embolism.

What are The Side Effects of Hydrogen Peroxide?

According to the American Dental Association (ADA), using hydrogen peroxide mouthwash at a concentration higher than 3% is unsafe. 

It can irritate your gums and other soft tissue, erode your enamel, or increase tooth sensitivity. However, these side effects are rare. 

Studies show that concentrations at or below 10% cause no permanent damage when used correctly. However, higher concentrations or longer-than-recommended exposure times can soften enamel over time.

How to Minimize Side Effects

Even mild whitening techniques can lead to discomfort if you overdo it. A few simple safeguards can keep your smile both bright and healthy:

• Keep at-home use to 6% or less. 
• Avoid keeping strips, gels, and pastes on for more than 30 minutes.
• Don’t use them daily
• Rinse thoroughly to remove it from gums and reduce sensitivity
• Space out whitening treatments by at least six months
• Follow product instructions and wear times
• Use fluoride toothpaste to remineralize the enamel

If your teeth feel tender or sensitive, take a break and consult a dental professional.

When It’s Essential to Consult a Dentist

You should always talk to a dental professional if you:

• Have existing dental issues, such as cavities or gum inflammation
• Have restorations like crowns, veneers, or dental implants
• Experience significant tooth sensitivity or pain when trying any whitening method
• Are pregnant or under 18
• Have stubborn intrinsic stains (e.g., from tetracycline)