Do serums ever go bad?

[Bonny]

While cleaning out a bathroom shelf, I found a small bottle of a heat protectant coney serum from a long long time ago. It's probably at least 5 years old. Can I still use it, or should I throw it out?

[hennalonghair]

coney serums are artificially made hence the silicones in them.
They also usually have preservatives in them to make them last. I don't know if silicones themselves have a shelf life or not .
You could open it and smell it. Even do a strand test but honestly, after 5 years I'd just toss it and buy another. Probably what you'll find is the silicones absorb the plastic the containers made of so no matter how nice the serum used to smell like they often end up smelling like the plastic it came in. This is one of those questions where the person really has to see touch and smell the product before answering.

[lapushka]

I have been using my IC Fantasia serums for about 3 years now (on and off one or the other bottle). Hasn't gone bad yet. I'd reckon they get gloopier when they get to their end, which is what happened with my CHI serum pretty fast. But it was still useable and I used it to the very end.

[Johannah]

I use Biosilk therapy once in a while (actually, when it freezes). I cannot even remember how long I have this one. Still works like a charm for this weather.

[meteor]

If the product fails the smell and texture tests, I'd toss it.

If the smell and texture is absolutely OK, it should be fine.

There's a reason why so many haircare products don't even have expiration dates printed on them in some international markets: they don't have "actives" that lose potency over time, and the preservatives really protect from bacterial growth.
Scalp treatments would be different (and should have expiration dates on them), as they contain actives.

[bonbon58]

I have been using my IC Fantasia serums for about 3 years now (on and off one or the other bottle). Hasn't gone bad yet. I'd reckon they get gloopier when they get to their end, which is what happened with my CHI serum pretty fast. But it was still useable and I used it to the very end.

My CHI serum is at least 5 years old, but it hasn't gotten gloopy or anything and I still use it

[Carolyn]

Smell it. Look to see if it has changed in color or consistency. If it passes those three tests then give it a try. If it performs as it used to, then go ahead and use it. Use your common sense.

[lapushka]

My CHI serum is at least 5 years old, but it hasn't gotten gloopy or anything and I still use it

Mine wasn't even a year, and the last 1/4th of the bottle almost didn't get through the little spout (it got clogged constantly).

[Bonny]

Thanks for all the responses, everyone! The old serum was still liquid, and smelled fine, so I think it's probably okay. I'll use it after my next hair wash and see if it still works!