How to take care of an overdose at home ???

So my friend her & her bf got into it & she took 11 Flagyl pills she was prescribed it was 500mg. She can’t go to the hospital because she doesn’t want them to keep her she didn’t mean to do it. She threw up once at 8 am she did it around 12am. How can i help her out at home she is feeling better pooping & everything hasn’t threw up since.