Unfortunately, this type of vandalism using food allergens does occur.  The quick thinking of the school's principal prevented many peanut allergic student's from being exposed to the peanut butter, but not all were spared.  One student had a severe allergic reaction as a result of this senior prank.

LA Times: Peanut butter pranksters may be banned from graduation ceremony

A peanut butter prank at a Sacramento high school landed a student in the hospital and may get others banned from graduation ceremonies.

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Aside from costing thousands in clean-up, the peanut butter slathered on doorknobs created a health crisis for students with bad peanut allergies.

Sacramento Bee: McClatchy High prank turns dangerous; 30 banned from graduation ceremonies

"That was an immediate factor because I knew several of our students have peanut allergies," said McClatchy High Principal Peter Lambert.

He said he called students with peanut allergies and told them not to come to school until later, but not all of the students were spared. "One student with a peanut allergy did come in and had a bad allergic reaction."