Most that give negative reviews fail to mention personal hair texture and scalp sensitivity. 1) keratin treatment isn't for everyday usage. If you use it everyday or every other day it may make your hair brittle (which will cause breakage). Try to wash and condition your hair no earlier than 6 weeks from initial usages (this goes for any keratin or kertain infused treatment & is based off your own hair texture). 2) if you have sensitive scalp consult with a professional, they may recommend a different brand. However, a sensitive scalp may get away with using the conditioner only. Keep in mind that a keratin treatment is for straighten and/or loosening curls; excessive usage is the same as over processing hair with dye, relaxers, perms, etc. Keep another shampoo and conditioner handy for your normal routine.
After having frizz proze hair I thought I would try this out. Not only does it dry my hair out, it also doesnt help with the frizz (I think it makes it worse). Highly disappointed!