Why is it ironic that Mama Elena dies from taking ipecac?

Mama Elena takes the ipecac to counteract what she believes to be poison on her food. Ironically, it is the so called cure that kills her.

But going through her bureau, they found the bottle of syrup of ipecac and they deduced that Mama Elena must have been taking it secretly.

John informed Tita that it was a very strong emetic that could cause death.