My shampoo had an expiration date.

[gomer_tree]

.

[erosewater]

For the same reason the bottle says rinse and repeat.

Why does bottled water have an expiration date? What happens to you if you drink expired water?

[Wannabe Actuary]

Originally Posted by gomer_tree

Why?

perhaps the chemicals in it react differently over time?
maybe something breaks down and it won't lather for you or something...

[Actuary321]

Originally Posted by SykoChikka

Why does bottled water have an expiration date? What happens to you if you drink expired water?

It can actually go stale. Which is why if you store water for emergencies you must rotate. It probably won't kill you but you may not want to drink it and it may make anything cooked with it taste funny/awful.

[ahow]

Originally Posted by Actuary321

It can actually go stale. Which is why if you store water for emergencies you must rotate. It probably won't kill you but you may not want to drink it and it may make anything cooked with it taste funny/awful.

And I think over time, it picks up tastes from the plastic bottle...

[Bob the Nob]

Originally Posted by ahow

And I think over time, it picks up tastes from the plastic bottle...

Is this the shampoo, or the water?

[CAPTAIN_MORGAN]

TO ENSURE A STEADY FLOW OF $$$ IN, A COMPANY WILL PUT EXPIRATION DATES ON THINGS SO THAT PEOPLE WILL BE GAURANTEED TO RECYCLE THEIR SUPPLIES EVERY 2 MONTHS TO 2 YEARS, OR WHATEVER THEY DEEM APPROPRIATE TO GUARANTEE SMOOTH CASH FLOWS. IT'S JUST A GIMMICK. HARRRRRRRRRRRRRRRRRR!!!

[Super Silver Haze]

http://www.realsimple.com/realsimple...676079,00.html

That doesn't give an answer, but it will create a lot more questions.

Vinegar??

[cubedbee]

If it's an anti-dandruff shampoo, then the active ingredient, zinc pyridinethione, is considered a drug, and as such must legally be labeled with an expiration date. If it's a regular shampoo, then that's just stupid.