I have long, tail bone length blueish greenish hair. It's fairly straight with a small natural wave. I've never had to wash my hair much, once every 3 to 4 days really. Recently (3 weeks ago) I've been put on a new medication, and it has affected my skin (dried it out and caused more breakouts) so I don't doubt it could have messed up my scalp. Unfortunately, I can't really go off of the medication because it manages my anxiety.

Anyway, so I guess my question is is there any washing technique that will help my hair be less greasy again, without/minimally stripping my hair of its unnatural color?

Sorry for how jumbled this sounds, I'll answer any questions anyone has. Thanks!