Should I tell someone?

I’m worried my friend is becoming bulimic/ anorexic.

She told me that when she regrets eating something or eating too much, she will take this medicine that makes her throw up. The medicine is her old birth control that didn’t work cuz , well, it made her get sick every night. But she still has a bunch of packs from the pre order thing.

When she told me she didn’t think it was a big deal but I’m kinda worried. Should I talk w her or tell someone or do you think it’s no big deal and it’s okay?