What ingredients make products unsafe for color-treated hair? (shampoo, dye, salon)

[trustmeiknow]

I know I'm supposed to buy shampoos and conditioners that say they are for color-treated hair, but if a product does not indicate this, are there certain ingredients I can look for that are known to strip away color? My hair is dyed now for the first time in a long time and I still have some products I bought when my hair was its natural color. I would like to know if I can use some of the old products still or not. For example, I have a Frizz-ease Rehydrating Conditioner that is full and new, and I would like to still use it, but it doesn't specifically say "color safe" on it. Anybody have any tips?

[moved]

Don't buy drugstore shampoo. Buy salon quality from a beauty supply store. It costs more, but it's worth it in the long run.

[pitt_transplant]

I wondered this too after you asked. I guess its anything: (list in link)

Surfactant - Wikipedia, the free encyclopedia

EverPure Moisture Shampoo by L'Oréal Paris
^^^ but there is a whole line that has a frizz serum too.
I have not tried it but maybe someone else has?

Loreal shampoos (vive) have been the only drugstore brand that I would used on colored if you don't get salon stuff.

I would not use the conditioner you have just incase it does not work out. I think the shampoo & conditioner makes the biggest change in color and condition. Styling products so so...they just seem to be a little drying on colored hair to me. I feel like it takes away the gloss really quickly. The shampoo/conditioner being regular types seems to pull a lot of color off my root area and dry out the ends. NOT a good look. LOL SO don't do that to yourself.