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Asked by kellyt - 7 years ago
I have some old shampoo lying around and I'm wondering if it's ok to use it. How long does shampoo last anyway?
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ilovegoogle Level 10 / Product Manager
Answered 7 years ago
Take a look at the bottle to see if has a picture of what looks like an open can with the words "12M" or "24M". This shows you the lifespan of your open bottle in months.

The shampoo that I use happens to have 24M on it. I bought a large bottle and I it usually last me close to a year. It's good to know that it could last up to 2 years.

The only thing you have to be careful with Shampoo is like many lotions and cosmetics, keep it away from direct sunlight or extreme heat since it can start breaking down. Also, make sure that the cap is closed so that the active ingredients don't evaporate into the air.
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Richard Level 79 / Retired Dentist
Answered 7 years ago
They probably contain DEA or Diethanolamine, Propylene Glycol, SLS or Sodium Lauryl Sulfate, and SLES or Sodium Laureth Sulfate.
There is still unveiling evidence that SLS produces a potential carcinogenic effect in your shampoo when it interacts with other nitrogen bearing ingredients to form nitrosamines ornitrates.
There is little regulation as to what might be in them.
But you are not going to be in contact with them long and you are going to wash it off. I think you can use the looks all right and smells all right test. I have seen shampoos look grungy in 6 mo. or maybe it took a year. If they have darkened in color, they are not going to slide right on your hair. Chunk those. If they are sealed tight and have not been exposed to temperature extremes, they could last a long time.
WillardRamirez Level 2
Answered 3 weeks ago
i think 10 minutes max.
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