Exactly as the subject line says I have a half-orc (barbarian background) who can't raise his charisma stat above 17 I'm confused and I'd like some help to fix this. Also I'm level 15.
IIRC, your max stat is determined by the racial/background bonus/penalty. Half-Orc with Barbarian background probably has -3 CH.
You can't remove the limitation, but there are thereapeutic items that can boost charisma which you (if you have the tech ability) or Jayna can make.
Do therapeutics get around the ceiling, though? I always thought it was fixed; for example, I've used the vivifier on someone with maxed out strength and dex, and it didn't raise those stats any further.