I wouldn't be surprised if she had an ulcer before taking the pills and it irritated them or she has an especially sensitive system as some do. I say this most

I wouldn't be surprised if she had an ulcer before taking the pills and it irritated them or she has an especially sensitive system as some do. I say this mostly because it is common (though not recommended) to take them on an empty stomach and it seems her reaction to the single pill does was extreme.