Teeth whitening strips - Common side effects and how to manage them.

- Thermal sensitivity. | Gum irritation. | Treatments and remedies. | Ways to prevent and control side effects.

Dealing with side effects caused by whitening strips.

Common problems.

By far, the two most common side effects people experience when using whitening strips (like Crest Whitestrips®) are  1) Tooth sensitivity  and  2) Gum irritation. This page outlines remedies for both of these complications.

Less frequently, a person may experience throat irritation, sore throat or even stomach upset. This page discusses remedies for these side effects too.

(Some people will notice uneven whitening, or white spot formation on their teeth following treatments. We discuss these issues on this page.)

Side effect avoidance.

The lower portion of this page provides some basic guidelines you can use to minimize your risk of experiencing side effects, or get them under control more quickly once they have started to appear.

1) Tooth sensitivity.

Studies suggest that between 1/3 and 1/2 of all people who use Crest Whitestrips® will experience some degree of tooth sensitivity. This is on par with that level typically reported for other peroxide-based whitening methods.

Section references - Gerlach


Whitestrips Supreme has the highest concentration whitener.

Crest Whitestrips Supreme.

Using a lower concentration strip can help to reduce side effects.

a) Why does it occur?

The cause of the sensitivity can be multifactorial. But one major component typically has to do with irritation (inflammation) of the tooth's nerve by the strip's peroxide whitener.
In general, the more concentrated the strip's whitener, the more likely it is that this effect will occur. (So, if you're searching for the "strongest" or "quickest working" strip, you may be setting yourself up for a fall.)

Section references - Gokay

b) What's the pain like?

In most cases, the sensitivity that's noticed is a heightened reaction of your teeth to hot and cold items, such as foods and beverages. Dentists call this "thermal sensitivity."

How much pain can you expect? When?

Especially in the case where you're using a strips product that's been coated with a comparatively lower-concentration whitener (here are examples of Whitestrips® products and their hydrogen peroxide concentration), the sensitivity usually just comes on gradually.

It may be persistent, possibly increasing a little each day with each treatment. Or just be noticeable for those first few hours following a bleaching session. With more potent strips, you may notice the sensitivity immediately upon the completion of even your first treatment.

Effects on activities.

Since the amount of sensitivity that results is usually relatively minor, and setting it off fairly easy to avoid, experiencing it typically doesn't cause great disruption in a person's life. Or even necessarily interfere with their bleaching schedule.

A review of dental literature by Gerlach found that with the 13 studies evaluated, only 1% of subjects discontinued their treatment process early due to tooth sensitivity or oral irritation.

Section references - Gerlach

c) Remedies for tooth sensitivity caused by using whitening strips.

1) Some improvement should occur naturally.

In the majority of cases, a person should notice that their thermal sensitivity begins to fade, a little each day, once they have completed their bleaching treatments.

Performing whitening sessions less frequently or using a lower concentration strip (such as Whitestrips® Gentle Routine) can help to speed this process along. - More information.

Toothpaste 'for sensitive teeth' can often cure tooth sensitivity side effects caused by teeth whitening strips.

Using desensitizing toothpaste, before or after problems occur, can help.

2) Try using desensitizing toothpaste.
You may be able to control the level of sensitivity that you experience by using an over-the-counter anti-sensitivity (desensitizing) toothpaste.

Many manufacturers make an anti-sensitivity version of their regular paste. These products are often labeled with the phrase "toothpaste for sensitive teeth." Their active ingredient is frequently potassium nitrate or fluoride.

(Related page: The best toothpastes for treating tooth sensitivity.)

Obtaining relief may take some time. - The idea is that you use the toothpaste in place of your regular one, for some days and weeks, as it gradually produces its effect.

(Prescription-strength fluoride toothpaste or gel prescribed or dispensed by your dentist can also be used in a similar fashion.)

3) Preventing tooth sensitivity.

As a way of helping their patients reduce their risk for experiencing thermal irritation, many dentists recommend that they begin using a desensitizing toothpaste two weeks prior to initiating the use of their whitening strips.

2) Gum irritation.

Studies suggest that between 1/3 and 1/2 of all people who use Whitestrips® will notice some degree of gum tissue irritation.

Section references - Gerlach

a) Why does it occur?

Gum irritation is caused by the caustic nature of the peroxide found in a strip's whitener. In general, the higher its concentration, the greater the likelihood that this side effect will be noticed. (Once again, a reason why the "strongest" or "quickest working" type of strip doesn't necessarily make a good choice.)

Teeth-whitening strips can cause gum irritation.

The cause of whitening strip gum irritation.

1) The shape of strips is part of the problem.
Unlike the scalloped shape of a person's gum line, the edges of a whitening strip are relatively straight.

And this means that when it is positioned over the user's teeth, some of its full-strength whitener will be in direct contact with their gums.

2) Residual whitener can be the cause too.

Gum irritation can also result from deposits of whitener that are left behind after a whitening strip has been removed.

For this reason, you should always rinse, wipe and/or gently brush your teeth and surrounding gum tissue after every bleaching treatment. Be sure to wash your hands and toothbrush off afterward.

b) How much discomfort can you expect?

In most cases, the level of gum irritation that a person experiences is just mild. It usually doesn't interfere with their daily activities, or even their bleaching schedule.

c) Remedies for gum irritation.

In the typical case, whitening strip gum irritation will gradually disappear over the next few days after the person's bleaching treatments have been completed.

Don't brush first.

You might be surprised to learn that Crest® does not recommend that you brush your teeth before applying Whitestrips®. Brushing tends to remove the protective microfilm that accumulates on gum tissue. Use that link to learn more about this effect.

Choose a different type of strip.

Performing sessions less frequently or using a lower concentration strip product (Crest Whitestrips® Gentle Routine) can help to keep this side effect in check. - More information.

d) The whitener may irritate your fingers.

Besides just your gums, a strip's whitener can also irritate your skin. We discuss this phenomenon in greater detail here.

3) Throat irritation.

Just like with any peroxide-based system, if the whitener from a strip is swallowed, throat irritation may occur.

And unique to using this method, there is also the potential that a strip might be swallowed. Doing so can result in throat or stomach irritation. (We discuss what to expect and do if you've swallowed a strip here.

Section references - crestwhitesmile.com

Preventing sore-throat side effects.

As a general rule of thumb, anything foreign that's placed in your mouth will tend to trigger increased salivation. So when strips are worn, especially during your first several sessions, you may notice this effect.

The accumulating saliva will tend to pick up some of the peroxide whitener that's leached from your strips. And if you swallow it, it will tend to cause throat irritation. So the solution is to avoid swallowing, at least to the extent that's possible. Instead, always spit fluids out.

Of course, despite your best efforts you will still end up swallowing some peroxide. But if you can keep this to just a minimum, the hope is that it won't be enough to cause throat or stomach irritation.

How using strips might help to lower your potential for throat irritation.

When whitening strips are made, a very measured amount of peroxide is placed on each one. That's in stark contrast to other at-home bleaching systems where it's the end-user who dispenses the amount of whitener.

In the latter case, like when using bleaching trays, the amount of agent that's dispensed, and therefore ultimately consumed, may be fairly significant. So by choosing to use strips instead, you may substantially reduce your potential for soft tissue irritation because you have less peroxide exposure.

Remedies for whitener-induced sore throats.

If the source of your throat soreness is the simple cause and effect we describe above, you'll usually find that your condition is self-limiting (which means that as hours pass you should notice ever-decreasing irritation).

And as mentioned above, if experiencing this side effect becomes a reoccurring issue for you, you can probably lower your risk by choosing a kit that comes with lower-concentration strips. Wearing your strips less frequently (like every other day) may help too.

Also, be sure to remove any residual whitener from your teeth after treatments (using a wet toothbrush is a good method) and rinse out thoroughly.

Guidelines for managing side effects.

a) If you notice side effects, stop your whitening treatments.

If side effects start to show up, it only makes sense to stop performing whitening treatments (right now, immediately).

There's absolutely no reason not to.

Bleaching teeth with peroxide is simply a function of whitener concentration and total treatment time (session length X number of sessions).

Interrupting the process for a few days, as you evaluate your side effects and allow them to subside, will not compromise your results (assuming that at some point you are finally able to finish using all of your strips).

b) Re-evaluating your whitening approach.

Once your side effects have subsided, you'll need to make a decision. Should you resume your treatments, or have the side effects you've experienced put you off on the whole idea of whitening your teeth.

If you do decide to continue on, you now have experience with what doesn't work. So, what you need to do is come up with a plan that can help to reduce the chances that your side effects will return.

Crest Whitestrips.

One pair Crest Whitestrips (upper/lower).

1) Try wearing your whitening strips less frequently.
One plan that can be successful is to continue on with the use of your strips but perform treatment sessions less frequently.

You'll simply have to experiment to see what regimen works best. For example, if wearing them every other day still triggers side effects, try every 3rd day. Or whiten on consecutive days until symptoms start to occur, and then back off on treatments for a while.

And don't worry, as we discussed above, performing sessions less frequently won't interfere with the bleaching process, it will only slow it down. Assuming that you still use all of your strips, you'll reach the same lightening endpoint.

2) Try using a lower-concentration strip.

Another solution involves using strips that are coated with a lower concentration whitener. For example, instead of using one of Crest®'s standard 10% hydrogen peroxide strips, try using their 6% one (Crest Whitestrips® Gentle Routine).

Different than with our example above however, by using a lower concentration strip your total exposure to bleaching agent will be less. If so, you'll achieve less whitening success.

3) Which approach is better?
To get a relative idea of which approach might be best for you, simply do some calculations. For example:
  • Crest Whitestrips® Professional Effects (10% hydrogen peroxide whitener, 30-minute application, 20 sessions) - 10 hours of total exposure of a 10% product.
  • Crest Whitestrips® Gentle Routine (6% hydrogen peroxide whitener, 5-minute application, 28 sessions) - 2.3 hours of total exposure of a (roughly half as strong) 6% product.


Clearly, these two products couldn't possibly be expected to produce the same whitening outcome.

So, in the case where side effects have become a problem for you, you'll need to decide:

  • If your teeth just need a little improvement, the Whitestrips® Gentle Routine product would probably make a good choice.
  • But if your teeth need a lot of improvement, you might either use Whitestrips® Professional Effects but spread out over a longer time frame. Or consider ultimately using more than one box of the Gentle Routine strips.


Evaluating your risk for side effects.

Start out slowly.

A smart way to test your potential for experiencing side effects is to ease into the use of your product.

For example, if their directions recommend daily treatments, do an initial one and then skip a day. If you notice even a hint of problems developing, continue on with this routine (or less) as you figure out to what degree they'll become an issue.

Faster and whiter isn't better.

If you're trying out teeth whitening strips for the first time, choosing a product that boasts that it gives faster and brighter results may not make the best choice, at least in terms of avoiding side effects.

These types of products tend to be ones that have a higher concentration whitener, or are intended to be worn for extended time frames (possibly even an hour or more). Both of these characteristics tend to make experiencing side effects more likely.

As a less risky alternative, look for a standard "introductory" type of product that's made by a well-known manufacturer.


 Page references sources: 

crestwhitesmile.com - Whitestrips FAQ

Gerlach RW, et al. Vital bleaching with whitening strips: summary of clinical research on effectiveness and tolerability.

Gokay O, et al. Peroxide penetration into the pulp from whitening strips.

All reference sources for topic Teeth Whitening Strips.


Crest Whitestrips

I found this very helpful I'm glad you had this for me to read I was starting to get very concerned with my irritation in my gums after using this product. Now I will continue to use it every other day. thank you


That sounds like a good plan. As you seem to understand, the whitening effect you receive is simply a function of how much your teeth are exposed to the whitener. So doing the strips daily or just every other day (so to reduce the level of side effects you experience) will result in the same level of whitening effect because the same number of strips have been used.

Sore throat

I only did the treatment once..and woke up to a burned out mouth...my taste buds feel burned..my throat is sore...I don't know how to fix it and feel better.


We're under the impression that this phone number 1-800-492-7378 can be used to contact Procter & Gamble about difficulties experienced with their Whitestrips products. You shouldn't hesitate to contact them.

From your post it's unclear exactly what has transpired.

If you've fallen asleep during your treatment, it would seem that while sleeping you've instinctively swallowed your saliva that contains the Whitestrips peroxide whitener, thus causing your sore throat. If you've slept for longer than the recommended treatment time, it would seem your whole mouth has had too much exposure to the peroxide, thus creating its irritation.

With this scenario, it would be expected that the irritation would be self-limiting (fade away as time passes). An oral analgesic (like Chloraseptic) might help to keep your mouth and throat more comfortable during that wait.

If it's the situation where you had completed your treatment before going to bed, possibly some amount of residual whitener remained on your teeth, thus causing the irritation you noticed.

While less uncommon, the situation could exist where you personally have a reaction to the compounds in the strips and therefore cannot use them. The Proctor & Gamble phone number above might shed some light on this possibility. We advise you to contact your dentist or doctor for an appropriate plan of treatment and subsequent evaluation.

Teeth Whitening Strip

Thanks for this huge information. This is actually very helpful for people using teeth whitening strip.

Bleach on everything.

After placing strips on my teeth I felt a warm burn on my cheek. Later on I found I had touched and spoiled the surface of my cosmetics case. For others ... YOU MUST WASH YOUR HANDS AFTER APPLYING WHITESTRIPS BECAUSE THEY WILL HAVE THE BLEACH ON THEM.


Thanks for reinforcing this point, side effects and unfortunate events can be caused by the whitener that gets on your finger tips during whitening strip placement. All packaging should be disposed of securely and your hands must be washed off after application.

Teeth burning

After using this product my teeth started hurting and along the whole mouth top and bottom. Is there any way recommend to lower the pain level

* Comment notes.


Above on this page we discuss side-effect issues like you've experienced and how to minimize or avoid them.

Orange Discoloration

Hi, so i've used white strips before. I've always noticed my teeth were a light yellow and super close to being white and I used the strips to boost the whitening process. I messed up big time. I used them as directed on the box and on the packet. I took them off and a day or two later, my canine teeth were a pumpkin orange color and all the teeth that touched the strip were yellow and orange. all my other teeth? they were light yellow and white. I'm very insecure about my smile as is and for me to put my trust into a product just for this to happen really makes this worse for me and the amount of breaking down about this is ridiculous. Somebody help me.


We're not going to have any explanation or remedy to suggest. Here's the contact us/helpline page for Crest Whitestrips. Hopefully they can provide you with some assistance.

1st you should for the first

1st you should for the first 10 days if there is no sensitivity. If there is sensitivity then skip a few days in between.
Use it till you get desire white and then just touch up once an a while.
Brush with good toothbrush and good toothpaste.
If you do have sensitivity use sensodyne toothpastes.

Discomfort Issue

Hello. I've used 2 sample strips one was standard and the other Luxe, did not use in same day every 3 days with very mild effects like teeth sensitivity. So, after the first time started again 4 days later with the Luxe and no problem. September 1st used Crest 3D White Whitestrips Luxe Professional Effects received them yesterday by mail and from viewing package directions and materials have a question. I have hsv1 which affects my bones to the point of arthritis like pain. My teeth are yellowish and noticed the strips are doing a great job in lightening them but after this use my entire jawbone aches to the point of a headache. Only had them in for 30 minutes then stopped. Should I seek further advice from denist /doctor if its wise to continue? Considering my health status? Any advice or suggestions will be greatly appreciated. Thank you fo your consideration and patience.

* Comment notes.


If you have experienced problems yet still want whiter teeth, then it would seem prudent to seek the advice of your dentist and MD to get their opinions about the cause and possible work arrounds. What follows are points and issues that we think should be considered and discussed with them.

There are a number of types of circumstances that tend to trigger the activation of the herpes virus.

Possibly exposure to the whitening agent acts as a trigger for you. If so, possibly using a strip that has a lower concentration whitener would allow you to continue treatments yet not be so strong as to activate the virus. (Crest Whitestrips Gentle Routine is a lower concentration strip. Possibly using it for less that the full 30 minutes would also be less likely to trigger your virus.)

The overall whitening effect you ultimately get correlates with your total exposure to the whitener (concentration and time). So with "gentle" strips, especially if used for short treatments, the whole whitening process will take longer (greater number of strips and weeks). But this routine may make it possible to whiten your teeth at-home where otherwise you couldn't.

We will also say that different than with all at-home whitening techniques where the whitener comes into contact with soft tissues and is also swallowed, in-office whitening technique (professional treatments in your dentist's office) offers the advantage that the whitening agent is only applied to tooth enamel (no soft tissue contact nor any systemic exposure takes place).

Hopefully your dentist and doctor can find a work around for you. Good luck.

Use prior to and after dental work

Hi-the box says not to use whitening strips 2 weeks before and 2 weeks after dental work--why?


Effects from the bleaching process can affect the bond strength of new restorations.

New silver (amalgam) restorations may be more prone to leaching mercury.

Healing soft-tissues (like following extractions, gum treatments, etc...) may be irritated by whiteners.

* Comments marked with an asterisk, along with their associated replies, have either been edited for brevity/clarity, or have been moved to a page that's better aligned with their subject matter, or both. If relocated, the comment and its replies retain their original datestamps, which may affect the chronology of the page's comments section.

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