A potion?

Kazimeriz looked at her, alarmed. "Miss Toussaint, you absolutely must tell me what the potion you took was, and where you procured it." If she had brewed it herself, perhaps she had gotten it wrong. He had seen it happen before, most notably when poor Brittany Dunstan had tried to take a potion to alter her regrettably large and unfortunately bulbous nose, but had mistaken erupment horn for bicorn horn in the brewing process. The child's nose had popped completely off her face and began running wildly , finally being captured six days later hanging around the ovens where the House Elves had just finished baking the daily bread. The child's nose was reaffixed to her face, but for the rest of her life she found that it would run intermittently at night, so she had to bind it with charms and even elastics before she could sleep.

Poor Brittany Dunstan. At least the constant running finally got the nose into decent shape.