Crest White Strips: Do They Work After Expiration?

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Crest White Strips utilize hydrogen peroxide as their active ingredient, which is a strong oxidizer known for its whitening effects. However, hydrogen peroxide is unstable and can lose effectiveness after the expiration date. While some users may still find expired strips somewhat effective due to the formulation, it is generally advised not to use them past their expiration date. Signs of degradation, such as an inflated package, indicate that the product may no longer be safe or effective. Users report positive results when the strips are used within the expiration period.
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First of all the chemistry behind crest white strips, do they actually work?

I have a package of Crest White Strips Premium plus my friend gave me from his work they have expired are they still effective after expiration date?
 
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Check what active ingredient is - that's answer to both your questions :wink:

Hydrogen peroxide is a strong oxidizer - so it may work. It is also unstable - so they can be not effective after expiration date, or at least less effective.
 
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I would not use it after the expiration date.
 
Hydrogen peroxide decomposes at a fast rate in water, I would still use the product since these strips have Hydrogen Peroxide imbedded in something other than water, however they may not be a great as one which has not exceeded the expiration date. Observe the package , if it seems inflated , than it's probably no good.
 
My mother swears by them, they definitely work... within the expiration date, at least.
 
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