I've only had it for a couple of weeks, and for right now, I am only using it as a sealant for my baggy on my ends. I haven't gottent the nerve to use it all over my head yet b/c I am trying to get used to the smell. It doesn't smell bad, but it's just one of those smells I have to adjust to. So far, I haven't seen any adverse side effects, but for me, the smell lingers. That's the only thing I don't like, but I will still continue to use it.