The Growth Factors serum is 100% safe for use on color-treated hair. However, I always advise that all first-time users apply a small test patch and leave overnight to test for any unknown allergies or effects on color. I have as yet had no reports of bad reactions, allergies or any effect at all on color and all of the ingredients are tested and known to be safe.
From my and my customers’ perspective, the serum is the best thing we’ve ever tried. Every day my hair gets thicker and thicker. I certainly recommend it.
If you have any questions, please let me know and I’ll be happy to help.