I thought the same here's my full theory: Due to preserving the bloodline over the generations the power has thickened, and the power has been concentrated into her body. Causing her to fall ill whenever she doesn't eat the pills to suppress it, since her body can't stand all the power.
Just a wildin’ theory on what her pills do but WHAT IF THEY HAVE BEEN HOLDING HER POWERS BACK??? Probably not but one can hope ╮( ̄▽ ̄)╭